The breakthrough

by Gigantic Mr.B

One lapse in concentration sets off an unstoppable chain of events for an 18-year-old lab intern, Ben.

5 parts 18k words Added Apr 2022 Updated 10 Sep 2022 33k views (#288) 4.8 stars (42 votes)

Part 1 One lapse in concentration sets off an unstoppable chain of events for an 18-year-old lab intern, Ben. (added: 9 Apr 2022)
Part 2 Ben meets Jack for lunch and begins to realise just how eventful his morning had been… (added: 16 Apr 2022)
Part 3 Ben and Jack return home as more explosive revelations come to light… (added: 30 Apr 2022)
Part 4 Following Jack’s unexpected growth spurt, both he and Ben plan their next moves...but which heads are doing the thinking? (added: 3 Sep 2022)
Part 5 While Ben and Jack are lost in their own lust-fuelled world at Jack’s cabin, Zach (Jack’s bigger bro) makes a big discovery at home... (added: 10 Sep 2022)
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Part 1

The sun had barely risen on what was sure to be another typically dismal day and already things had gotten off to a bad start. Standing at a meagre 5’7” and weighing barely 110 pounds at 18 years old Ben was used to mockery and humiliation. In particular Ben often found himself as the punching bag of his dumb, overly-muscled jock of a step-brother, Jace, and his equally brutish step-father Dan. Before Ben had even made it downstairs for breakfast, Jace had already taken the opportunity to torment him by barging into the bathroom in all his naked glory right in the middle of Ben’s shower.

“All right, shrimp-dick, get your scrawny arse out of here before I drag you out,” Jace laughed as he yanked back the shower curtain and smirked at the sight of his almost comically small step-brother.

Scrambling to cover himself up lest his inadequacies be made even more obvious, Ben couldn’t help but steal a few quick glances at Jace’s perfectly sculpted body and mightily impressive package. He hated himself for it but Ben couldn’t deny his obvious attraction to his step-brother’s muscle-bound body.

“Hey, what the fuck Jace! I’m in the middle of showering, you can’t just walk in here and kick me out whenever you choose,” cried Ben, certain his protestations would have little effect.

“Oh yeah,” replied Jace as he flexed his impressively large bicep in front of Ben’s face. “Well, this says I can do whatever the fuck I want little man”, he laughed with his trademark smug grin plastered across his face.

Ben’s eyes were transfixed on the bulging biceps in front of him, momentarily forgetting himself, before regaining his composure and noticing his mistake.

“Oh shit, are you getting a hard-on little man?” Jace roared with laughter. “That’s fucking pathetic, look at what a real man has to work with,” Jace mocked as he gripped his own member, easily a couple of inches bigger soft than Ben’s measly boner.

Feeling his face flush red and a wave of embarrassment and shame wash over him, Ben scrambled for a towel to cover his pitiful frame and ran out of the bathroom before his humiliation could get any worse. As he returned to his bedroom he could hear Jace’s laughter continuing behind his back as his step-brother climbed into the shower. Despite himself, and his humiliation, Ben couldn’t help but picture his tormentor soaping up and rubbing his meaty pecs and arms and stroking the monster between his legs. He hated to say it, but Jace was everything Ben had ever wanted to be, standing at over 6 feet tall and easily over 200 pounds of pure, testosterone-fuelled muscle with a perfect jawline, thick layer of stubble and just the right amount of body hair Jace was, in Ben’s view, the ultimate man.

Hating himself for still being turned on by his step-brother despite the abuse he suffered at his hands, Ben hurriedly got dressed and ran down stairs hoping to grab some toast and head out before he had to come face to face with Jace again. As he headed out of the house to begin his daily walk to the biolab he was interning at, Ben found himself wishing, not for the first time, that his efforts at the gym would show even the slightest hint of paying off. Though his lack of physical prowess was beyond doubt, Ben more than made up for those shortcomings in the brains department. Having graduated from high school as valedictorian Ben had been afforded the opportunity to intern at the nearby biochemical research facility in the break between his graduation and starting university. Biochemistry was not Ben’s favourite field of study, having always been more intrigued by the humanities than by the sciences, but he had decided to take up the offer anyway in the hopes of finding a way to help his physical development along. While it was a long-shot he still harboured hope that one day some miracle drug, growth virus, super-hormone or….whatever really, would come along and make all of his wildest dreams come true.

As Ben walked, savouring the quiet and reflecting on the morning’s unfortunate events, he heard someone approaching from behind. Turning to see who it was Ben found himself giving an unexpected piggy-back as the man jumped on top of him.

“Duuuuuude, what’s up!” said the man in a voice Ben instantly recognised.

“Just the usual…now, do you mind getting off my back before you snap me in two?” Ben chuckled as he turned to face his best-friend, Jack.

Ben and Jack had grown up together and been firm friends since their first year in school. Both being the skinny, underdeveloped type they bonded pretty well and had stuck together ever since. Jack, unlike Ben, was tall…very tall, standing at 6’5”—he even had a couple of inches on Jace. Unfortunately that was the only physical edge he had, in every other way Jack was more similar to Ben, being painfully skinny, awkward looking and definitely more brains than brawn. Jack was a tech wizard, whilst Ben’s skill lay in the world of academia, Jack was a master with technology and, as such, he too had been offered a place with the bio-lab, working in the IT department making sure the various computer systems and bits of equipment were running smoothly.

“Soooo…you any closer to creating your super-soldier serum?” Jack teased, knowing all about Ben’s desire for muscle growth.

“No, do you think I’d still look like this if I was?” Ben replied somewhat tersely.

“Whoa, no need for that tone. I’m only messing,” said Jack, slightly amused at how seriously his friend appeared to take the idea of creating some sort of super serum.

“I know, I know… I’ve just had a bad morning is all. I’ve been mocked more than enough for one day already, thank you very much,” replied Ben, allowing himself a small grin at his best friend’s taunt.

Little did Jack know, Ben had been working towards finding a scientific solution to his physical woes for some time. Of course, he’d already considered the various options produced by science thus far, but none of them were capable of producing the kind of results Ben truly desired both in terms of mass and timescales. No, Ben hoped to find a much better way forward. One that would cut out the need for dietary restrictions, endless hours in the gym and the usual ‘blood, sweat and tears’ mentality. Fortunately, one of the projects he had been assigned to at the lab was focused on hormone treatments, specifically aiming to increase the size and fertility of livestock. Of course, none of these experiments were fit for human testing yet but their very existence opened up the possibility of such treatments being made possible for human use too.

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As Ben and Jack rounded the corner to the laboratory’s car park they agreed to meet for lunch and went their separate ways, Jack heading for one of the side-buildings that housed the IT department and Ben heading straight through the main entrance, flashing his ID to the security guards and swiping his key card as he walked through barriers. Racing up the stairs he donned his lab coat and stored his belongings in the locker room before heading to the main lab to receive his tasks for the day.

“All right there, Ben?” asked Mark, one of the lead researchers on the project.

“Not bad. Just want to get my head into some work, if that’s okay?” replied Ben, hoping to be assigned to one of the research labs where he could spend the day in his own company before returning home to the taunts and jibes of his step-family.

“Fine by me. Why don’t you head over to lab 4 and administer the new compounds to the test specimens? We need to get them started soon if we want to progress to the next phase of the trial on schedule,” replied Mark casually.

“Wait…y-you want me to administer the serum? I would have thought you’d want a more senior researcher on that,” stuttered Ben, unsure whether he’d heard correctly.

“That’s right, I think you’ve proven yourself reliable enough to be trusted with this. Besides, if you have any trouble we’ll all be right here, just come and find someone,” Mark gestured over his shoulder towards the others.

“Oh… okay then, I’ll get right on it,” Ben replied, not quite believing his luck.

The rest of the morning went smoothly, after settling into a good routine Ben was powering through the test subjects. Measure, administer, observe… move on to the next, taking a break each hour before doing a quick check over the specimens already treated and returning to administer the serum to the others. About an hour before Ben’s usual lunch break he felt his phone buzz in his pocket.

Huh…nobody ever texts when I’m at work, he thought to himself absent-mindedly as he placed the needle he was holding on the counter and reached into his pocket in search of his phone. As he pulled the phone from his lab coat the screen came to life showing the text notification… from his step-father. Already knowing this was unlikely to be good news, Ben reluctantly unlocked the phone and tapped on the message. It read:

‘You fucking pervert, Jace told me all about what happened in the bathroom this morning. Think you can burst in on my son whilst he’s in the shower, tugging that little faggot dick of yours, and get away with it? I’m gonna beat the shit outta you when you get back here tonight…’

Ben’s face drained of colour as he read, the realisation of what Jace had done hit him like a punch in the gut. Ben could feel himself begin to tremble, panicking about how he was going to get out of this situation, knowing Dan would never believe him over Jace.

“Oh shit oh shit oh shit…” he mumbled as he fumbled around his phone, trying to text Jack to let him know what had happened. A few moments later Jack replied, assuring him that things would be okay and offering to let him stay over for a few nights until his step-dad had calmed down.

‘Just focus on your work and I’ll see you at lunch in an hour, we’ll figure this out…’ Jack signed off.

Not even remotely reassured by his friend’s response, Ben tried to follow his advice anyway and return his focus to his work. Stowing his phone back in his pocket, he reached out to the counter, hands still unsteady, and retrieved the needle before turning to the latest test subject and injecting the serum. As Ben turned to the counter in search of the sharps bin he noticed a small spec of blood forming on one of his fingertips.

“Oh no…no no no no…this is all I need,” Ben muttered to himself. Though certain he had not injected the entire syringe into himself, rather than the subject, he must have pricked his finger with the needle inadvertently. There was no telling how much, if any, of the serum he’d been exposed to. Rushing over to the sink, Ben scrubbed his hands hard hoping that any residual serum would be washed away before it had the chance to be absorbed. Still reeling from his step-fathers text and now worried about his slip up with the serum Ben decided he needed to take an early break to clear his head before his lunch with Jack. Heading out of the research lab and locking the door behind him Ben noticed he was burning up, despite the relatively cool conditions of the laboratory his forehead was beaded with sweat and his cheeks were flushed pink. As he hurried down the corridor towards the bathroom his skin felt like it was on fire as a wave of dizziness struck him at full force, reaching out to steady himself against the wall he felt a hand land on his shoulder.

“You okay there… Ben, can you hear me?” It was Mark. Trying to pull himself upright and regain his composure Ben turned to face his boss.

“Yes, I’m fine… thanks. I just need some food… skipped breakfast… just… just taking a break,” stumbled Ben in reply.

“Are you sure? You really don’t look very well…” questioned Mark. Ben nodded his head. “Well, if you’re sure. But don’t be afraid to go home for the day if you need to,” said Mark before giving Ben a pat on the back and striding off.

I think I’m having a panic attack…my clothes feel too tight, I feel like I can’t breathe, Ben thought to himself as he staggered through the bathroom door. Feeling another wave of dizziness come over him he reached out and steadied himself on the sink just as his whole body seemed to tense up, pain searing across his skin, his clothes feeling ever tighter. As the dizziness began to subside Ben’s focus began to shift towards his crotch where his package was coming under severe pressure from his boxer briefs. Looking down he could see a small drop of pre-cum leaking through his trousers….

“What the fuck is going on?” Ben moaned as he turned around and headed for the stalls. Quickly undoing his belt and dropping his trousers in order to save them from the now constant stream of pre-cum and relieve some of the pressure on his junk, Ben stared in astonishment at his drooling cock. Unable to help himself he reached down and began to stroke slowly at first, with his cock seemingly more sensitive to his touch, before steadily picking up the speed and tightening his grip as his feelings of panic and anxiety were replaced by pleasure. Stroking up and down, lubricated by the river of pre-cum he’d produced, feeling every throbbing vein and each pulse of his engorged cock Ben lost himself in a world of ecstasy and lust. Breathing heavier and heavier as he neared climax he began writhing uncontrollably, responding to the waves of pleasure that were spreading throughout his body as he continued to furiously jerk off his member. Finally after what felt like an eternity he couldn’t hold back any longer, letting out an uncharacteristically deep, even primal, groan as a torrent of thick, hot cum burst out of his cock, coating the inside of the stall and drenching his lab coat entirely.

Slowly coming back to his senses, Ben looked around him at the mess he’d caused, his jaw dropped at the almost inhuman amount of cum he’d produced. Realising he needed to act quickly if he had any intention of salvaging his clothes Ben sprang into action, whipping off his lab coat and using it to mop up as much of his seed as he could. Grabbing handfuls of paper towels in a desperate attempt to clean up the remaining puddles of cum and dry himself off before leaving the stall, he dumped his saturated lab coat and boxers into the bin and headed back over to the sinks. As he did so, he caught sight of himself in the large bathroom mirror… though he couldn’t figure it out exactly, there was something different about the way he looked, almost as though he was seeing himself from a different angle.

Shrugging it off as an after-effect of his momentary dizzy spell earlier on, Ben leant down and turned on the tap to splash his face with some cold water. About halfway down Ben felt the uncomfortable sensation of his clothes pinching once again, this time just around his shoulders and ass. Giving himself a closer inspection in the mirror he could see that his clothes were indeed fitting a little more snugly than usual.

“Huh, must’ve picked up an old shirt and trousers by mistake this morning,” he muttered to himself, blaming his eagerness to get away from Jace for his apparent carelessness. After spending a couple of minutes splashing some cold water on his face and composing himself after what was possibly the most epic orgasm he’d ever witnessed, Ben patted his face dry and left the bathroom, minus his boxers and lab coat, and headed over to meet Jack for lunch…


Part 2

As Ben strode across the entrance lobby of the lab on his way to the canteen for lunch with Jack he couldn’t shake the feeling that something was different. He couldn’t put his finger on it exactly but his body felt different, heavier somehow, and he still couldn’t shake the feeling he’d had in the bathroom that everything around him seemed to be slightly out of scale. Again, Ben simply shrugged it off putting these nagging thoughts down as nothing more than the after effects of the stress of the morning’s very strange events. The day had started off badly and had managed, somehow, to get worse at every turn. Ben’s mind dwelled on the text message he’d received from Dan and the tall tale of his ‘so-called’ perversion that had been spun by Jace, though admittedly it was, regrettably, partly true with the humiliation of springing a boner at the sight of Jace’s bulging arms washed back over him. Trying to turn his mind back to work didn’t help much either, his slip up with the serum only an hour or so earlier still weighed on Ben’s mind which was swirling with all of the possible outcomes. Concern was his dominant emotion, thinking of all the negative side effects that could come with an early stage, experimental compound intended for livestock…but there was a small part of him that was a little bit too excited at the prospect of a super-serum coursing through his veins. His earlier conversation with Jack seemed a little more serious than it had only a few short hours ago.

Finally, Ben entered the canteen, scanning the sea of tables in search of Jack’s familiar face as he helped himself to some lunch. Just as he had earlier that day Jack popped up behind Ben unexpectedly, only this time he seemed to not recognise his lunch companion right away, bumping Ben’s arm accidentally.

“Sorry about that, mate…” Jack apologised absent-mindedly as he continued to peruse the various dishes on offer.

“Uhhh…hello! Earth to Jack…” replied Ben, surprised and amused in equal measure that his best friend of more than ten years seemingly hadn’t realised who he’d bumped into.

“Oh, have we met befo—” Jack started before the realisation of who he was talking to hit him.

“Haha uhhh yeah, I’d say we’ve met once or twice,” Ben joked back, confused as to why Jack was acting so strangely.

Ben! What the fuck…what happ—…how did…what?” shouted Jack, his eyes wide with shock, attracting more than a few surprised and disapproving looks from those seated nearby.

“Do you mind? Why are you acting like a weirdo?” asked Ben, mightily confused at his best friend’s strange outburst.

“Uhhh…have you seen yourself lately? Like…maybe in the four hours since we last spoke?” replied Jack, his voice dripping with incredulity.

“What are you talking about?” countered Ben, looking himself up and down. “If you’re talking about my lab coat then it’s a long story.”

“I’m not talking about your fucking lab coat, you dweeb. I’m talking about your…your muscles and…height. You look ready to burst out of those clothes!” rambled Jack, pausing after each observation to ogle Ben’s body.

“Oh, yeah…I must’ve picked up an old shirt this morning in my rush to get out of the house. I noticed it earlier but it’s really not a big deal, I promise you I’ll dress more appropriately tomorrow…” joked Ben.

“Ben, I don’t think you’re understanding me. Those clothes fit you fine this morning…in fact, that’s your favourite shirt! You wear it all the time!” replied Jack, astounded by his friend’s apparent lack of awareness.

“Wait…you…you’re right, it is my favourite shirt. How…” Ben tailed off as he stared down at his torso, finally waking up to the reality of his situation.

“How indeed…you’ve got muscles now Ben. Not just that, you’ve grown all over…look at how tall you are,” prompted Jack, squaring himself up to his friend in order to confirm the new height difference.

“Holy shit…I’m just a few inches shorter than you now!” Ben marvelled as he took note of the narrowing height difference between himself and his formerly towering companion. Amazed that he’d not realised his increased height immediately, Ben took a little longer to look himself over this time, raising his arms and flexing his newly developed muscles. At some point over the course of the morning he’d gone from being a short, scrawny weakling to a six foot something beefcake. He was by no means ‘big’, certainly still not a match for Jace, but his usual painfully skinny arms had been replaced by firm round biceps, his boney chest now sported two nicely defined pecs and his abs were clearly defined through the tight fabric of his now ill-fitting shirt. Ben stared and ran his hands over his new body, akin to the lean and tight physique one would normally see on an elite swimmer.

Ben was snapped out of his reverie by the disgruntled mumblings of a group of lab workers who were standing nearby, realising that he and Jack had now been holding the line up for the last 5 minutes. Quickly apologising to the waiting diners and filling his tray with whatever was nearest Ben turned away from the counter and headed towards a table right in the back corner of the canteen with Jack, who was still lost for words, following close behind.

“Okay, you need to tell me what’s going on…right now,” said Jack seriously as they sat down at their table.

“I honestly don’t know what to tell you,” Ben began. “I didn’t even realise this had happened until you just pointed it out to me.”

“There must be something that’s happened this morning…you don’t just fucking shoot up in height and pack on pounds of muscle at random,” Jack scoffed as Ben began to tear through his sizable tray of food at a frightening pace.

“Well, I did have a minor incident in the bathroom just before heading down here but it’s not like I just sat there and started growing,” replied Ben, recounting the confusing and, admittedly, arousing events that had occurred less than an hour earlier.

“Wait…you felt ill, went to the bathroom and then you plastered the inside of a stall and saturated your lab coat with cum?” confirmed Jack, astonished at the tale he’d just heard. “You don’t think maybe you should have started with that?”

“Okay, okay…you’ve made your point. I get it, it’s weird but in the moment I couldn’t think straight and once it was over I didn’t think much of it. I feel fine now and I certainly didn’t realise I’d changed or…grown,” Ben replied, slightly exasperated, through mouthfuls of food.

“Well, whether you realised it or not, you have definitely grown…there must be something you remember, something that happened to cause this,” Jack persisted.

“Not really…it was a pretty standard morning up until I started feeling funny. Well, except from the death threat text from my step-dad but I don’t think that would cause me to start growing at random,” explained Ben, taking himself back over the morning’s events. “Unless…no, no I can’t be,” he ruminated.

“Well…what can’t be? What is it?” Jack insisted.

“Promise you won’t freak out?” Ben asked tentatively, putting his fork down for the first time since they’d sat down.

“Oh…I don’t like the sound of this,” said Jack as his face dropped.

“Well, you remember when I texted you about Dan? I was pretty shaken up thinking about how fucked up the whole situation was and I tried to follow your advice and focus on my work but…but my hands were shaking as I administered one of the new hormone treatments and I accidentally pricked myself with the needle,” rambled Ben, barely pausing to take a breath. Jack’s face darkened as he took in what Ben was saying. “I mean, it’s not like I injected myself as such. It was really just a pinprick and besides the serum hasn’t had any effect like this on any of the samples…so…it can’t be, surely it can’t have done this to me. Right?” Ben continued.

“Ben. Please, please tell me this is some kind of joke…” Jack replied, his voice barely audible.

“I’m not joking, Jack,” Ben replied solemnly, as he once again began to shovel food into his mouth.

“This is fucked up, you realise that? You accidentally injected yourself with an experimental super serum and an hour later you’re growing and cumming like a fire hose and now you’re eating like a…well, you’re eating a lot,” Jack pointed out.

Now that Jack mentioned it, Ben realised just how hungry he had been and just how messed up the morning’s events sounded when he heard them laid out. Thinking about the situation he found himself in, the growth, the insane jerk off session in the bathroom, his ravenous hunger…Ben couldn’t help but wonder how much further the serum could take him, if it was indeed the serum that had caused these unexpected changes. This is what he’d always wanted, this could be the chance to realise all of his wildest muscle filled dreams…so why did he feel so unnerved?

“Well, when you put it like that,” Ben replied, his mind again abuzz with possibilities, as he felt a familiar tug at the crotch of his pants. “Oh no, not again,” he sighed.

“What now?” asked Jack, rolling his eyes.

“I’m…I’m getting hard again,” answered Ben, his eyes gesturing down towards his crotch. Jack’s eyes widened as he realised what Ben was implying, glancing under the table his jaw dropped.

“Uhhh Ben…when I said you’d grown everywhere…well, it appears I really did mean everywhere,” said Jack, his voice tainted with shock and more than a little jealousy. Ben glanced down himself, taking in the sight of his now sizable, throbbing bulge.

“Oh shit…how big did it get?” Ben asked aloud, the sight of his impressive bulge only turning him on more.

“This is turning you on, isn’t it? Ben, just think about this before you do anything stupid,” warned Jack, evidently concerned about the possibilities Ben saw opening up infront of him. Jack, much like Ben, had always been attracted to muscle and growth but had never come close to Ben’s level of fascination and desire.

“Oh fuck, not now Jack. The last thing we need is for me to go full cum fountain in the middle of the canteen,” Ben moaned, a small spot pre-cum already leaking through his trousers. “There’s only one way to know for sure what’s happening to me…I’m gonna go run a blood test in the lab and find out once and for all. I’ll meet you out front in half an hour, we’ll have to take a day off until we’ve figured this thing out,” said Ben, desperately trying to take his mind off the monster throbbing in his trousers.

“Yeah, I think that might be a good idea…” agreed Jack, standing up to clear away the food trays.

“Oh…Jack, I might need to borrow your hoodie…better take the jacket as well,” apologised Ben.

“Fine, but I’ll want those back…and don’t get cum all over them like you did your lab coat! That jacket is expensive!” said Jack before letting out a long, resigned sigh. Ben hurriedly donned the hoodie, wearing the hood up in an attempt to disguise himself as much as possible, the last thing he needed now was for Mark or one of his other colleagues to recognise him and start asking questions. Standing up he quickly covered his crotch with Jack’s jacket and strode off out of the canteen towards the research lab avoiding making eye contact with anyone on his way out. Scurrying nervously up the stairs towards the lab, Ben was keenly aware of his unsubsiding erection and the rapidly growing patch of pre-cum currently seeping through his trousers. Seeing a supply cupboard up ahead Ben rushed along the corridor and entered in search of a lab coat or apron…anything to cover up the obscene sight of his engorged bulge. Seeing a rack of lab coats, Ben selected the largest size available hoping to cover himself up as much as possible as he continued on to the research lab. Buttoning the lab coat all the way up Ben’s bulge and pre stains were, thankfully, covered…for now.

Racing down the last stretch of corridor leading to the research lab he’d been working in that morning, Ben gave a small sigh of relief having made it there without being spotted. Scanning his key card the door swung open and Ben stepped through, the throbbing of his bulge becoming almost unbearable.

“Oh fuck, I can’t take this anymore…” he moaned, unzipping his trousers and letting his engorged member spring upwards making a satisfying thud as it hit his abs.

Jesus…how did I not notice the size of this thing in the bathroom earlier? It must be easily 10 inches and these balls…fuck they’re like lemons, Ben thought to himself as he scanned the room for an appropriate receptacle to release his load into. Spotting the water dispenser in the corner Ben had a wild idea, leaping forward and emptying the gallon water tank out over the sink he thrust the tip of his cock through the rim of the emptied vessel and finally unleashed the torrent of cum he’d been holding in his balls since leaving the canteen. The force behind his ropes of cum took Ben by surprise as he allowed himself to fall back against the door for support, unable to stifle his deep, guttural groans of satisfaction. Finally, after more than half filling the gallon water tank, Ben’s erection subsided. Completely drained and in a state of ecstasy Ben forced himself back into reality and stuffed his junk back into his trousers before carefully placing the cum filled tank on the floor so as not to spill any and leave any incriminating evidence. Still out of breath from the intensity of his orgasm Ben staggered over to the counter and pulled out a testing kit from the cupboard, filling the test tube with testing solution and placing it in the rack. Pulling out a fresh needle in order to draw some blood from his fingertip the irony was not lost on him that a pinprick to the finger may have been exactly how he ended up in this situation in the first place.

Steadying his hands, Ben gently pricked the end of his finger and allowed a few drops of blood to drip into the testing solution before disposing of the needle and retrieving the activating agent. Ben added 10 drops of the activating agent into the test tube before putting the stopper in and shaking to combine the solution. There, now we wait… he thought to himself as he stowed the test tube and a testing strip in his lab coat pocket. As he disposed of the test materials, his eyes landed on the drugs locker containing the serum samples…all it would take was one swipe of his key card and he could fulfil all of his wildest dreams. Feeling that pang of arousal once more Ben let his lust overrule his logic and opened the locker, reaching up he grabbed a handful of the capped, pre-prepared syringes and stuffed them into his other lab coat pocket. Whirling around and reaching for the door, Ben had just made it across the threshold when he remembered the tank filled with his cum sitting on the floor of the lab. Turning back to retrieve it he caught sight of Mark heading up the stairs at the bottom of the corridor. Determined not to be discovered now, Ben grabbed the cum filled container, wrapped it as best he could in Jack’s jacket to conceal its contents and raced towards the stairs at the opposite end of the corridor.

A few moments later, after dodging several members of the lab’s staff, Ben finally reached the car park and saw Jack waving to him from across the lot. Ben had never felt as much relief in his life as he did at that moment, he hurried over to his waiting friend and breathed a sigh of relief.

“Hurry up, I’ve got us a car!” yelled Jack.

“Wait…how did you find a car in the space of half an hour?” gasped an out of breath Ben as he reached Jack’s position.

“Called in a few favours, borrowed it from one of the tech guys…Is that yo—” Jack began.

“My cum? Yeah…I wasn’t gonna make it and I couldn’t very well leave this behind so I guess it’s coming with us,” explained Ben, unable to stop himself from chuckling at the absurd situation he’d found himself in. After a few moments, Jack began to chuckle too realising how insane the day’s events had been.

“This is fucking madness…get in before someone starts asking questions,” Jack managed in between his bursts of laughter. Ben headed to the rear passenger door and stowed his cum filled gallon jug in the back seat and strapped it in before jumping into the front passenger seat and doing his own seatbelt up.

“Why the fuck are you strapping your cum bucket in…it’s not a baby,” asked Jack, clearly amused.

“Of course it’s not, but we can’t leave it here and I don’t think your friend would appreciate you returning his car covered in my cum…would he now?” replied Ben matter-of-factly.

“Yeah, okay…I’ll give you that one,” conceded Jack as he climbed into the driver’s seat and turned the ignition. “My place?” he asked.

“Definitely your place,” agreed Ben, as Jack pulled away.


Part 3

Relieved to finally be out of the lab, away from prying eyes, and on his way to Jack’s place Ben’s mind was racing as he replayed the day’s events in his head. Not only did he have to find a way to deal with the situation at home where he was pretty sure his step-father wanted to kill him, he also had to deal with the matter of his unexpected, though not entirely unwelcome, growth spurt. Yet another reminder of the bizarre situation he found himself in was the half gallon of cum he could hear sloshing around in the back seat. Strangely, Ben found the sound calming…almost like being at the beach and hearing the gentle waves crash onto the shore. As his mind drifted, letting go of his worries for a brief moment, he realised his hand had found its way into his lab coat pocket and was currently fidgeting with the test tube that would tell him whether or not he had exposed himself to the serum. Immediately, his mind began to whir again, mulling over all implications of his momentary lapse in concentration. What would be the long term effects? How was he going to explain this to Mark…hell, how was he going to explain this to his family? What if the lab called the police?

It was at that point Ben’s stomach sank as he remembered what was stowed away in his other lab coat pocket. Kicking himself for allowing his state of arousal back in the lab cloud his judgement so completely, Ben slowly shifted his hand down towards his pocket, tracing the outline of the pre-prepared needles he’d stolen from the drugs locker. One…two…three…four…five… Five full syringes of experimental serum now lay in his possession. Though he’d been concerned about how the lab would react to his situation before, the full realisation of what he’d done in stealing the serum samples slowly began to dawn on him. In the space of 30 seconds, with his brain scrambled by the intensity of his almost superhuman orgasm, Ben had managed to potentially throw his entire life away. Once the lab realised the samples were missing, they’d check the security system and see it was his key card that had last accessed the drugs locker…this key card evidence combined with his strange behaviour in the corridor when Mark had come across him doubled over, sweating and dizzy, would surely lead to Mark putting two and two together and realising what he’d done. That would be that…the police would be called, he’d be arrested and taken away in handcuffs, set for a life in prison. Unless…

Ben once again found his mind, and hand, drifting back to the five serum filled syringes in his lab coat pocket.

‘It would be so easy…’ Ben thought to himself, ‘Just one drop has blown me up to this size…imagine what just one full syringe would do’. As Ben allowed himself to indulge his muscle-fuelled fantasies for a moment, he found himself asking ‘Would I really want that life…to grow that much, become a freak of nature…nobody would ever mock me again, I could be unstopp-’.

“Uhhh…Ben, you’re not gonna…y’know, again are you?” asked Jack, looking over at Ben’s crotch nervously, cutting short Ben’s muscle-fuelled fantasising. Following Jack’s eyeline down to his crotch, the cause of Jack’s concern was clear. Once again, his newly enhanced member was throbbing in his pants. ‘Damn! Got a little carried away there I guess…’ thought Ben.

“Oh, sorry man…No, I think I can hold it, just please tell me we’re not far from your place,” replied Ben as calmly as he could, not wanting Jack to pick up on how turned on he was at the thought of more growth.

“Nah, we’re only a couple of minutes away,” replied Jack. “Surely you can’t be that horned up already…you shot a half-gallon load not an hour ago.”

“Man…you have no idea,” sighed Ben as he gazed out of the passenger side window.

A few minutes later Jack pulled up onto the drive of his house, unbuckling his belt and hopping out of the car. Making sure both the test tube and the syringes were still safely ensconced in his pockets, Ben followed his friend in jumping out of the car.

“Don’t forget your cum,” Jack jibed, gesturing towards the back seat of the car where Ben’s half-gallon of cum still sat.

“Yeah yeah, I got it,” retorted Ben, opening the rear door and grabbing the half-filled water tank. Shaking his head at the sheer absurdity of the situation Ben turned on his heel and followed Jack up the drive to the house. “Wait…are you sure no-one’s home? I don’t think your parents would appreciate me roaming around with a half-gallon of cum in one hand and a raging boner in the other…” Ben asked Jack, only half-jokingly.

“Yeah, no worries. They’re both away on a business trip for at least a week and Zach should still be at work,” replied Jack, assuring Ben that they wouldn’t be interrupted by Jack’s parents or, indeed, his big brother.

“Silver linings…eh?” Ben replied with a small chuckle. Stepping through the front door Jack turned and beckoned Ben to follow, heading through the hall and straight up the stairs. Ben was always impressed when he visited Jack’s house, unlike his own home Jack’s house was huge and immaculately kept. Both of Jack’s parents were successful business people and had amassed a small fortune through their myriad business dealings.

“I think the first thing we need to do is get you out of those clothes and deal with…that situation,” said Jack, pointing towards Ben’s engorged, leaking bulge.

“Uhh yeah, good idea,” nodded Ben.

“You can use my room and en-suite to get cleaned up, try to keep your cum off my carpet though…I’ll go and grab some of Zach’s old clothes for you, should fit better than what you’ve got on at the moment,” said Jack, nodding toward the door to his room.

“Yeah, thanks man,” said Ben as he headed towards Jack’s bedroom door, his need to release becoming increasingly urgent. Ben hurried through Jack’s room and made directly for the en-suite, not at all confident in his ability to not blow his load all over Jack’s expensive soft furnishings. After closing the en-suite door behind him and carefully draping his lab coat on the towel rail, Ben tore off his once loose fitting shirt and quickly undid his belt, dropping his trousers. To his surprise, and delight, rather than simply dropping to the floor, Ben found himself having to work his trousers down over his newly plump ass and thickened quads. Standing there, fully naked, in front of Jack’s full-length mirror Ben was able to take stock of his new physique properly for the first time. Gone was the stick thin, boney runt Jace had mocked so ruthlessly earlier that day and in his place was a tall, strong, toned physique. Ben explored his improved body with his hands, relishing the feeling of his well-defined pecs and abs, savouring the feeling of his powerful legs as he tensed his quads seeing the striations come to life.

“This is insane…I look like like a star fucking athlete,” Ben marveled aloud, bringing his arm up and flexing his newly formed biceps and triceps, watching on with excitement as a modest ball of muscle popped and seeing the horseshoe of his tri’s come to life with every flex. “Fuuuck….” Ben groaned in pleasure, unable to resist jerking his thick, veiny cock any longer. Almost instantly Ben was again overcome by the intensity of the sensation, feeling himself go weak at the knees, and staggered over to the walk-in shower, allowing himself to collapse to his knees. Grunting with pleasure Ben continued to pump his engorged cock, giving in fully to the almost primal urges he was feeling. One hand on his cock, the other continuing to grope and explore his firm, hard muscles as they flexed and tensed with exertion. Lost in his own world of lust and pleasure Ben didn’t hear Jack enter the bedroom and knock on the en-suite door.

“Ben? Ben, you good in there?” Jack called, hearing Ben’s groans and grunts through the bathroom door. “Alright, I’m coming in…” Jack warned, leaving a few seconds before turning the handle and entering the en-suite.

The sight that met Jack’s eyes was nothing short of obscene, he looked on in astonishment, unable to speak, as he watched his once scrawny best friend jerk off one of the biggest cocks he’d ever seen. Every single strand of every single muscle on Ben’s body was visible, flexing powerfully as his friend relentlessly beat his meat. “Ho-ly Fuck,” whispered Jack, barely able to muster his voice into action.

“Yes….fuck yes…more, come on…ohhhhh fuuuuuck!” Ben roared as he finally released his load. Jack had never seen anything like it. Ben’s cock was shooting rope after rope of thick, hot cum with so much force he was sure they would have easily knocked a grown man to the ground. The stream of cum just kept on coming, filling the walk in shower floor, the drains unable to meet the demand as Ben’s hand continued to rhythmically pump the load out of his cock. After several speechless minutes, Jack saw Ben’s orgasm begin to subside, the ropes of cum tailing off and Ben’s strokes slowing. By that point Ben, kneeling in a pool of his own hot seed, was completely spent, his body finally beginning to relax as his heavy breathing began to slow. The entire bathroom reeked of testosterone…the smell of Ben’s cum mixed with a distinct musk was an assault on Jack’s senses, the combination of the sight, sounds and smells he’d just witnessed giving Jack a raging erection of his own.

“Fuck…that was…” gasped Ben.

“That. Was. Amazing,” Jack finished, still in awe. “Look at you…look at my fucking bathroom!” he cried.

“Oh shit, how long have you been there! Look, I’m sorry man I couldn’t help it. I was so horny on the way over here and then seeing myself in the mirror…I just…I lost control,” confessed Ben. “It felt so fucking good.”

“Don’t you dare apologise,” Jack admonished. “That was the single hottest thing I’ve ever seen in my life, you’re a fucking beast now!”

“Ohhh god, don’t say shit like that…I’ve only just got this thing to go down!” pleaded Ben, gesturing to the only semi-soft 10 inch dick that was bobbing up and down in between Ben’s impressive thighs.

“Sorry man, I just had to say it,” replied Jack, as he retrieved several towels from the rail and handed them to Ben.

“Thanks,” said Ben gratefully as he rose to his feet, cum and sweat dripping off him, and took the towels from Jack and began to wipe himself down.

“I’d normally suggest you take a shower…but I don’t think that’s an option right now,” noted Jack, gesturing to the lake of thick cum that was slowly gurgling down the drain of the shower.

“Yeah haha…I guess not,” replied Ben, slightly embarrassed by the mess he’d made in his friend’s bathroom.

“Well, dry yourself off as best you can and then we need to talk about what this means,” said Jack as he retreated from the bathroom, turning to give the almost unbelievable scene one more glance.

A few minutes later Ben emerged from the en-suite, having dried himself off and splashed his face with some cold water, still nude and timidly covering his impressive softy up with his hands. “Ummm…you forgot to give me any clothes,” Ben pointed out.

“Over there,” Jack smirked, nodding to a small stack of clothes on the desk chair, as he watched his friend shyly scurry over and attempt to dress himself as quickly as possible. “If those don’t fit I’m cool with you…y’know, going commando if you get what I mean,” suggested Jack.

“Yeah, I figured you’d say that,” Ben chuckled. “I saw your…reaction to me in the bathroom,” he said, his eyes drifting down towards Jack’s still very visible hard-on.

“Oh…well, you can’t really blame me…can you? You have to admit it was a pretty hot view,” Jack replied confidently, though Ben could see his cheeks blushing slightly.

“Okay then, have it your way,” Ben said, dropping the t-shirt he was about to put on, clearly enjoying the confidence boost his new body, and Jack’s flirtations, had given him. He sauntered over to the bathroom as confidently as he could and fished the test tube and strip out of his lab coat pocket before walking over to join Jack on the bed.

“Is that the test?” asked Jack as Ben settled himself next to him on the bed.

“Yup, time to find out once and for all…” said Ben as he removed the stopper from the tube and dipped the test strip into solution.

“Well, now what…” asked Jack, staring intently at the test strip in Ben’s hand.

“It should only take a few moments,” he said as a faint line began to appear at the bottom of the strip. “Well, there we go…the serum is in my bloodstream. Now we just wait to see how much I was exposed to.” The two sat there patiently waiting for any further changes in the test strip…five minutes, ten minutes and fifteen minutes passed without so much as a hint of change.

“Soooo…is it done?” asked Jack quizzically.

“Yup…good news and bad news,” responded Ben. “The good news is I was only exposed to a trace amount of the serum…”

“And the bad news?” prompted Jack impatiently.

“The bad news is even such a small amount has added half a foot in height, tens of pounds of muscle, massively increased my sex-drive and given me a horse-cock that cums like a firehose,” replied Ben. “Oh and I’m probably going to be fired from the lab, possibly arrested and am probably going to produce an ocean of cum every two hours until the effects wear off…if they wear off,” Ben added.

“Ah…I see your point. Although I would have thought you of all people would have been excited about this…y’know, except for the going to prison part,” Jack responded encouragingly.

“I don’t know Jack, I’d say the whole ‘me going to prison’ part is a pretty integral factor here,” exclaimed Ben, although his friend did have a point. He’d be lying if he said he wasn’t enjoying the effects of the serum so far. What scared him the most was how enticing he found the idea of taking more, growing more…all his wildest dreams were within his grasp, if only he could bring himself to reach out and take them.

“Look, it may not come to that. I’m sure the lab won’t punish you…I mean, it was an accident after all,” said Jack. Ben’s stomach dropped, regret and guilt flashed across his face. “This was an accident…right?” asked Jack, picking up on Ben’s facial expression.

“Yes! Of course it was an accident but…but me taking five syringes of the serum from the drugs locker wasn’t,” Ben blurted out. Jack’s jaw dropped, his eyes widening as he processed what Ben had just said.

“Ben…when you say you took five syringes…you mean you stole them or do you mean…” Jack faltered.

“Oh my god, I mean I stole them! I didn’t shoot myself up with five syringes of an experimental hormone drug, I’m not insa—” Ben shot back.

“Oh, you’re not insane? You stole five syringes of an experimental drug! I’d say that’s pretty insane behaviour,” raged Jack as he got up from his place on the bed.

“Okay, okay I agree… but in my defence I wasn’t thinking straight. You’ve seen the effect the serum has on me when I’m horny!” Ben explained. “Of course I can see how insane it looks now but at the time my dick was doing the thinking…not my head,”

“Oh…this is just great,” sighed Jack, shaking his head as he paced back and forth.

“Look, I know it’s not a great situation to be in but there must be some way to fix this,” pleaded Ben. “Can you not change the records or erase the key card data or… or something… anything?”

Jack continued to pace for a few minutes more before responding.

“Alright, alright…here’s what we’re going to do. I’ll log in to the lab administrator’s account and amend the records to hide the 5 missing syringes, I’ll try and erase the key card entry on the drugs locker for good measure,” explained Jack. “Meanwhile you need to contact the lab and tell them about the accident…there’s no other way to explain this,” Jack instructed as he gestured up and down at Ben’s new larger frame.

“Do you think they’ll buy all of that? There’s no way they could figure out what we’ve done?” asked Ben.

“If I’m honest, I don’t know. I’d say there’s a good chance that it’ll work but there’s no guarantee that someone won’t dig something up…at this point we have no alternative,” replied Jack, his voice filled with resignation.

“Okay then… I guess that’s that,” said Ben, torn between doing the sensible thing and throwing it all away in pursuit of his ultimate fantasies.

“Agreed… now, there’s no time to waste. Every minute we spend discussing this the chances of someone at the lab noticing the missing syringes increases. You need to go and find some clothes that actually fit you, Zach will be home soon, I’ll go and tackle the bathroom before it stinks the whole place out and then I’ll deal with the lab,” Jack practically ordered Ben into action.

“Right…where am I gonna find clothes that will fit?” asked Ben as he looked over at the crumpled pile of Zach’s old clothing that still sat on the desk chair.

“Try my Dad’s room, second door on the left,” Jack said, pointing towards the hall before turning his back to Ben, grabbing the cum-filled water tank that still sat on his bedroom floor from earlier and heading into his cum coated en-suite with a heavy sigh.

Feeling bad for the mess, literally and metaphorically, that he’d landed his friend in Ben strode from the room in search of some wearable clothes, his bigger unrestrained cock slapping the inside of his thighs as he did so. Walking into what he assumed was Jack’s fathers’ bedroom Ben headed straight to the walk-in wardrobe and looked for the baggiest clothes he could find. Though he was more lean than large, for now, Ben still wanted to try and hide as much of his newly developed musculature as possible, his increased height alone would be hard enough to explain. After around 15 minutes of trying various items of clothing on Ben had finally found a top and bottoms that were wearable, though he wouldn’t be scoring any points for style. After tidying away the unused clothes Ben headed back along the hall, freshly dressed, towards Jack’s room.

“Jack?” he called, as he headed towards the en-suite. Receiving no response Ben assumed Jack simply couldn’t hear him, or that he wasn’t talking to him, and swung open the door revealing his best friend writhing on the floor, cock in hand…growing.

“Ugggghhhh…fuck…no, no, no,” groaned Jack. Ben knew all too well what his friend was going through…burning up, pain searing across his skin, his muscles seizing up. Looking at his friend’s growth, he found it hard to believe that he hadn’t noticed his own growth spurt only a few hours ago.

Jack…you didn’t!” Ben yelled, lunging towards his lab coat, still draped over the rail, in search of the five stolen syringes. Much to his relief all five were there and remained intact, though that didn’t explain what was happening to Jack.

“I’m…I’m sorry…I couldn’t help it, it was just so…so overwhelming,” Jack managed to say in between his agonised groans of pleasure. “I had to taste it.”

Ben’s heart sank as he realised what had happened. The serum wasn’t only designed to increase size…it was also designed to increase virility. The increased volume of cum, the heightened sex drive, the larger genitalia…it all made sense now. An unintended consequence of the serum must have been to increase attraction to the subject by triggering a pheromonal response. The combination of Ben’s cum and sweat had driven Jack to need to taste his cum, not only that but Ben’s cum seemed to have similar properties to the serum itself. Were it not for the fact this was all taking place in Jack’s bathroom instead of in the lab Ben would be elated at this kind of breakthrough.

“It’s okay, just focus on cumming…it’s the only way to get it to stop!” Ben urged as he watched his friend’s body swell and stretch.

The already tall Jack was now positively huge, easily seven foot tall, his bony arms and legs thickening by the second, testing the seams of his clothing. Ben continued encouraging Jack to cum as his best friend’s pecs began to inflate at an alarming rate. Jack continued to stroke his lengthening cock with one hand as the other began to wander up his body, feeling the cobblestone abs and firm, defined pecs that had not been there only a few moments earlier. Watching this grotesque, but arousing, display of unabashed growth and self-worship, Ben felt his own manhood begin to stir once more.

‘Oh fuck…this can’t happen here! Not now!’ Ben thought as he grabbed the now emptied water tank and unzipped his freshly selected trousers, so as not to add even more cum to Jack’s already cum-fuelled growth spurt. As both Ben and Jack were gradually taken over by the effects of the serum, Jack continuing to swell and Ben once again in the throes of self-pleasure, the two men began to jerk themselves off in unison. Their animalistic grunts and groans echoed around the tiled en-suite as they both eventually began to cum. Enormous amounts of hot cum began streaming out of their two cocks, filling the bathroom and water tank all over again, before both of their orgasms subsided and left the two of them lost for words…


Part 4

“Fuuuuck…” Ben whispered under his breath as he surveyed the scene in front of him.

Looking around the en-suite it was difficult to find a surface that wasn’t coated in hot, white cum. Thick streams trickled down the shower screen, more had begun to pool in the bathroom sink, Ben could no longer see himself in the mirror that only a few hours ago he’d used to admire his new physique. A constant glug glug glug drew Ben’s attention to the freshly topped up lake of cum in the shower tray as it slowly, very slowly, drained away. In the middle of it all lay Jack.

Ben’s eyes wandered over his friend’s newly boosted physique. Jack had always been tall but now, at seven feet, he outstripped any man Ben had ever seen. Ben guessed that Jack had gained roughly the same amount of muscle mass as he had earlier that day, albeit spread more thinly over Jack’s much taller frame, and was freakishly lean. Even without flexing, every twitch, every striation of Jack’s new muscles was visible. His skin appeared paper-thin with a level of vascularity Ben had never seen before. Even the most extreme, freakily conditioned athletes couldn’t come close to Jack’s new physique.

As his eyes roamed over Jack’s new body Ben’s eyes were drawn to his friend’s monstrously thick cock. He’d never seen Jack’s manhood before today, though from ogling his bulge Ben had suspected what Jack lacked in length he made up for in girth, but the newly grown member his best friend was sporting now was truly outrageous. Ben doubted it would be possible to wrap his hand around it, and maybe he’d even be struggling to wrap both hands around it. He watched the beast continue to twitch and spasm.

Exploring Jack’s body, taking in the sheer freakishness of his friend’s physique, caused Ben’s own mighty member to twitch, pulling him out of his mental reverie and back into reality. As Ben turned his gaze away from Jack and back to himself he could see his own, still half hard ten-incher still dribbling the last remnants of cum all over his, or rather Jack’s father’s, trousers.

Oh for fuck’s sake, Ben thought to himself, placing the freshly filled gallon jug of cum back on the floor and reaching for a towel to try and clean himself up.

“Uhhh…I don’t think our original plan is going to work anymore,” Ben remarked, as he passed Jack the driest of the towels he could find.

“Oh really, whatever gave you that idea?” Jack replied sarcastically as he snatched up the towel and rose to his feet, careful not to hit his head on the light fittings. Now that Jack had stood up, Ben could truly get a sense of just how tall his best friend had grown, his head just scraping the ceiling of the bathroom.

“Jack…I…I don’t know what to say. I don’t know what we can do. How on earth are we going to explain this?” Ben replied apologetically.

“Well, there’s no going back now, is there? But we can’t stay here… not like this, not until we’ve figured out how we’re going to explain this all to everyone,” Jack said as he continued to try and towel himself down. Despite Jack’s outward display of frustration and concern over their now-shared predicament, Jack seemed to be remarkably calm beneath the surface. As Ben watched on, it looked more like he was indulging in an impromptu self-worship session than actually trying to clean himself up, subtly flexing his newfound muscle, his eyes lighting up as the thick stands of his quads danced underneath his skin or his pecs bounced as he dried himself off.

Hey!” Ben snapped. “Enough of that, the last thing we need right now is you setting yourself off again. We need to get this place cleaned up and work out what we’re gonna do about to fix this mess.”

“I know, I know…” replied Jack apologetically. “If you really don’t want to set me off again, maybe you should consider putting that away,” he added as he gestured to Ben’s own impressive manhood.

Damnit, Ben thought to himself as he hurriedly stuffed his junk back into his borrowed trousers. “I don’t think your Dad is getting these clothes back,” he remarked as he saw a small patch of residual cum soak through the front.

“Meh…it’s not like he can’t afford new ones. Besides, I think we’ve got bigger things to worry about, don’t you?” came Jack’s reply as he reached up to turn the shower on, hoping to wash away at least some of the potent mix both of their climaxes from his bathroom floor and shower. “You gonna help me out with this? After all this is ultimately your mess.”

“Uh…yeah, sure,” said Ben. He rolled up his sleeves and, grabbing the nearest towel, heheaded for the sink.

After what felt like hours the en-suite was finally, almost, back to the way they’d both found it. Despite what must have been at least a few gallons of thick seed washed down the drain, which both Ben and Jack secretly couldn’t help but feel was something of a waste, and a large bundle of towels and cloths dumped into the washing machine, one problem remained: there was no getting rid of the smell. A potent mix of sweat and cum hung in the air.

“Fuck, it still smells like an orgy in here,” complained Jack as he sprayed air freshener to little effect.

“Well, at least we’re not wading through cum anymore,” Ben replied, feeling his phone buzz in his back pocket. The screen lit up as he retrieved his phone from his trouser pocket displaying several missed calls and texts. “Oh no…no no no no,” he spluttered.

“What is it now?” Jack asked, exasperated.

“Mark has been trying to call me all afternoon, he’s left a text asking if I’m all right and if I’ll be in the lab tomorrow,” replied Ben, thrusting his phone screen in Jack’s face. “Look!”

“All right, all right…calm down, I’m thinking,” responded Jack, scratching his head. “He must not know anything is wrong at the lab—there’s no way he’d have found out five of his syringes are missing and messaged you that calmly. Which means we still have time.” He rushed over to his desk and opened his laptop.

“I’ll tell him we’re both ill and taking the rest of the week off,” Ben said as he texted, receiving little more than a grunt of acknowledgement from Jack, who by this point was typing and clicking at terrifying speed.

“Riiiight….right, okay…okay okay okay, I think I got to the records before anyone picked up on them,” Jack said as relief washed over them both.

“You’ve deleted it all? My keycard access to the lab, the drugs locker, CCTV…all of it?” Ben asked.

“Well, I’ve deleted the logs that show you as the last person to enter the research lab and access the drugs locker. But I can’t do anything about the CCTV without erasing the whole recording and that would definitely be noticed… besides by that point you were wearing my hoodie, covering your face and had grown half a foot, so I doubt anyone would recognise you even if they did see the CCTV,” Jack reassured him.

Just then Ben’s phone buzzed again. “Ah, there we go, Mark has authorised both of us taking the rest of the week off and said to ge—” Ben’s sentence cut off sharply as his phone buzzed yet again.

“What? What’s wrong, what else did he say?” inquired Jack nervously.

“Nothing, nothing…it’s just my step-dad again, cussing me out for not coming home and taking the beating,” replied Ben. Fuck…with everything else going on I totally forgot about the impending disaster waiting for me at home, Ben thought, grimacing at the seemingly growing list of problems he needed to deal with.

“Look, don’t worry about it. You can stay with me for a while until we get things sorted… Wait…you should have been home by now?” Jack yelped, his eyes widening in realisation as he scrambled for his own phone. “Oh shit, the time, Ben…we need to leave right now.” Jack leapt to his feet, almost smacking his head on the light fixture hanging from the ceiling.

Ben’s eyes widened as he realised what the problem was. “What time does Zach get back?” yelled Ben.

“Uhhh….like, right now. He’ll be here any minute,” said Jack as he raced back to the desk and gathered up his laptop and a handful of chargers before dashing towards the bedroom door. Ben followed suit and grabbed his bag and, most importantly, his lab coat with the stolen syringes.

“Jack, wait…” called Ben, his eyes gesturing towards the swinging monster cock slapping against his friend’s quads. “Maybe you should put some clothes on first?”

Jack darted back towards Ben and shoved his gear into Ben’s arms before striding across the room towards his wardrobe and throwing on the first things he found. He picked out a pair of long shorts and a plain tee that fit him more like short shorts and a crop top. Watching Jack attempt to fit into his old clothes would have been comical if their situation weren’t so desperate. Having (barely) covered himself up Jack strode back towards the door of his room, his obscenely thick bulge preceding the rest of his body by a few inches, and beckoned Ben to follow as he raced down the stairs and out onto the drive.

“Hurry up!” scolded Jack as he marched out to our borrowed car and attempted to cram himself into the driver’s seat.

“Umm…maybe I should drive this time?” asked Ben as he stowed their things in the car.

“Fine…I’ll get in the back,” replied Jack.

“So, we can’t stay at your place and we definitely can’t go back to my place…any ideas?” Ben asked as he pulled out of the driveway.

“Uh huh, remember that old cabin my folks used to take us to just outside of town?” Jack asked.

“Yeah…” confirmed Ben.

“Well…it’s kinda mine now,” replied Jack, nervously adjusting himself in his much too small clothes. “Well, my parents kinda bought it for me as a graduation present… it’s mine, I own it.” Jack had always been reluctant to talk about his family’s wealth, not wanting to come across as just another spoiled rich kid.

“Dude, that’s awesome,” Ben reassured him, smirking slightly as he watched his best friend struggle to adjust his clothing in the back of the car.

“Don’t be a dick,” Jack retorted, seeing Ben’s amused grin.

“Hey, I think you look cute in a crop top. It suits you,” Ben responded, winking at Jack as he did so.

“Well, thanks… I mean, I’d like to return the compliment but you’re kinda wearing my Dad’s clothes soooo…” Jack teased.

“Fair enough…” Ben started before he felt a now familiar throb in his crotch and looked down to see his impressive member begin to stir once again. “Okay okay, enough with the flirting, we’ve still got a drive ahead of us and I can’t steer this thing if I’m cumming like a fire hose,” he warned.

“Maybe not…but I’d like to see you try,” Jack retorted cheekily before sending his own manhood stirring to life.

“Jaaack, I’m serious,” Ben practically moaned, feeling his engorged cock press against the bottom of the steering wheel.

“All right all right, I’ll cut it out. So, what do you plan on telling your folks about your little growth spurt? Y’know your step-dad seemed pretty pissed with you already…” Jack said, hoping to distract them both from their throbbing boners.

“Oh fuck man, I don’t even know,” replied Ben, “To be honest I don’t know what we’re gonna do about any of this, I mean… look at you, you’re seven foot tall now.”

“Yeah, you don’t have to tell me,” Jack said, becoming increasingly aware of the uncomfortable position he was in just to fit in the back seat.

“I mean, we could just inject ourselves with a couple of those syringes and fucking grow… god, I’d love to see the look on Jace and Dan’s faces. Just think about it, with a full injection we’d be fucking gods… we’d have to explain ourselves to no one, never take shit from anyone ever again…” Ben rambled.

“Uhhhh…yeah, or we could not do that,” Jack laughed nervously, sensing Ben was taking his impromptu fantasising a little too seriously.

“Ha yeah, obviously I’m not being serious…” Ben scoffed. “I mean, look at us now… we’ve barely grown at all and look at the problems it’s caused… getting any bigger would just make things worse… unless… y’know…nnggghh... unless we grew so big that we could just do whatever we wanted, I mean who could stop us… hmmphh... we wouldn’t be able to hide but we wouldn’t have to man… uggghh... we could just grow and live like fucking kings,” Ben continued, his sentences interspersed with moans and groans.

“Okay there, buddy… gonna need you to tone it down,” Jack said as a growing patch of precum spread across the front on Ben’s trousers. Damn, I knew he was into muscle but this is something else, Jack thought to himself, not wanting to admit that the more his friend talked about growing, the more his own dick throbbed and twitched.

“Fuck, I know we can’t do it Jack… we can’t… but I’ve dreamed about something like this for years, man. You’ve got no idea how badly my body wants this, how badly I need this, even if it’s only a fantasy,” Ben explained, only half convincing himself that he could withstand the temptations.

“Look man, I get it… this is your thing, your ultimate fantasy yadda yadda, but you gotta realise it’s your dick doing the thinking right now, not your head,” Jack replied, only half convincing himself that Ben’s fantasies weren’t also his fantasies.

“Uggghhhh, I know… but you’re the same as me now, you know how fucking turned on I’m feeling right now… how turned on we both are,” Ben retorted, his eyes glancing back at Jack’s own leaking cock.

“Fuck… just… just get us to the cabin, we can empty our fucking balls again and then we can talk about what we do next,” Jack urged, fighting the urge to join Ben in his lust-fuelled imaginings.

By the time they reached the cabin, both of their cocks were leaking constant streams of pre. Their clothes, and the car’s upholstery, were soaked through and their discipline had rapidly diminished.

“Fuck… ugh... we’re… uhhhh... here,” Ben managed to gasp between his cock’s powerful spasms, barely keeping himself from blowing his load right then and there.

“Just… go… hmmphh get inside…” replied Jack as he opened the car door and started towards the cabin door, his monstrously thick cock almost fully exposed, having escaped from his laughably small shorts.

Ben threw open the car door and followed his friend towards the cabin, both of their impressive cocks leaving a trail of thick pre-cum in their wake. By the time Jack had managed to get the door to the cabin opened, both men were barely clinging on to rational thought, their focus now entirely on their throbbing cocks and new muscles. Within seconds the two, newly enlarged, best friends were all over each other. Jack lurched towards Ben and they quickly launched into the most frenzied make out sessions of their lives. As their two tongues wrestled and explored each other’s mouths their hands began to roam wildly over each other’s bodies, groping and tracing the now distinct musculature that adorned their frames.

Ben’s hands quickly ventured around to Jack’s stunningly muscled ass, feeling every slight twitch and squeeze of his best friend’s glutes as they continued to kiss. In turn, Jack had squeezed his hand in between their two bodies and was groping Ben’s pecs. The pleasure Ben and Jack were receiving from their joint muscle worship and make-out session was nothing compared to the sheer ecstasy the two men felt as their respective members rubbed up against one another. In their hurry to admire each other’s bodies their impressively erect cocks had become trapped between their two writhing torsos, rubbing against each other and coating their abs in a glistening layer of potent pre-cum.

Lost in a world of lust and self-worship the two newly enhanced men paid no attention to their phones, the buzzing and pinging of text and missed call notifications drowned out by the sound of their carnal grunts, groans and moans. Ben, still gripping and groping Jack’s stunning ass, felt his friend’s hips begin to grind and thrust against him sending waves of pleasure through his cock and body as he felt his own hips begin to gyrate in response. Unable to contain themselves any longer, both men’s loads began to erupt from their overstimulated cocks as they felt each other’s muscles tense and flex with exertion.

The sheer force of their shared orgasm forced the two men to the knees, their loads being shot with such force they found themselves, and their surroundings, coated in layer upon layer of hot spunk. Overwhelmed by the intensity of it all, both men roared in ecstasy and opened their mouths to taste each other’s seed. Without any thought about the potential consequences of their indulgence, the two men continued to lap up as much of their cum as they could, running their tongues over each other’s cum-coated body before their other-worldly orgasm finally began to subside leaving them both exhausted and dazed.

After what seemed like hours the two worn out friends finally began to stir from their shared, cum-fuelled stupor and surveyed the scene around them. Jack’s, formerly well presented, reeked of cum and sweat worse than any locker room either man had come across. They found themselves lying in a pool of their own still warm load, looking up at a similarly cum-coated ceiling, their tattered clothes lying around them having been torn off in the process of their wild encounter.

“Ho-ly shit…” Jack breathed as his eyes took in the scene, his facial expression and odd mix of horror and pride.

“Uggghh, how bad is it?” Ben groaned, not wanting to look for himself.

“Well, we didn’t break any furniture but there might be a few stains,” Jack offered in a half-hearted attempt at humour.

“Fuck man, how much cum did we drink! If it has anything like the effect my cum had on you we are soooo screwed,” Ben exclaimed, though Jack couldn’t help but notice the glint in Ben’s eye as he faced the prospect of another growth spurt.

“I don’t know, but if what’s left on my floor and ceiling is anything to go by I’d say we both had a much bigger taste this time round than I did back at my place,” Jack said as he began to rise to his feet, feeling his heavy cock slap against his thighs with a satisfying thud.

“I mean, how quickly did my cum have an effect on you after you helped yourself in your bathroom? Must’ve been pretty quick, I was only gone a short while…” Ben asked Jack as he too rose to his feet, careful not to slip in the thick puddle of cum at their feet.

“Uhhh it was pretty instant… I was cleaning, got hit by this overwhelming urge to taste your cum and then boom, a one-way ticket to growth-ville,” Jack recounted as he headed to the cabin’s bathroom to grab a couple of towels.

“Oh, so it looks like we’re safe then… no more growth for us today,” replied Ben trying to hide the disappointment in his voice as he reached out to take a towel from Jack.

“Looks that way, besides I think we’ve got enough to deal with for the time being without adding any more surprises into the mix,” Jack intoned disapprovingly, as he toweled himself down for the second time that day.

“It seems as though my cum…uhhh, maybe our cum, can only grow guys by the same amount I grew during my growth spurt. I mean, think about it, I grew around half a foot, went from skinny runt to lean athlete and added a good few inches to my dick…” Ben thought out loud as he gestured up and down at Jack’s new body.

“...and I also grew by half a foot, went from skinny to ripped and added a handful of inches to my dick,” Jack finished, feeling a wave of relief wash over him as he realised he wasn’t going to have to deal with any more unexpected growth spurts…for the time being.

“...*sigh*...he doesn’t give up, does he?” Ben said mostly to himself, “My dickhead of a step-Dad has left about a million messages describing how he’s going to fuck me up when I get back,” he explained.

“Like I said, you can stay here as long as you need. Anyway, I’ve got a feeling your step-father is going to be the least of your problems in the next few weeks,” replied Jack as he reached for his own phone. As he unlocked his phone Jack felt the colour drain from his face.

“Jack? You okay?” Ben asked worriedly.

“Shit shit shit…” Jack blurted out as he began furiously tapping away on his phone screen.

“Jack! What’s wrong?” Ben demanded but Jack just shushed him.

“Zach! Do not touch that, ring me back right now!” Jack yelled frantically down the phone before ending the call and going back to texting faster than Ben had seen anyone text before.

“Oh….oh no,” Ben whispered as he realised what had happened.

“We left a gallon of your super-serum cum in my house! Look!” Jack panicked as he thrust his phone in Ben’s face. On the screen Ben recognised the familiar surroundings of Jack’s bedroom and right in front of the en-suite door sat one full to the brim gallon jug of growth-inducing seed. Beneath the image was Zach’s text: ‘Uh bro, what the fuck is this?!’.

“Fuck…” said Ben.


Part 5

Zach’s perspective—a few hours earlier

Zach paced impatiently back and forth behind the reception desk of the gym as he waited for his shift to finish. Just ten more minutes and then I’m outta here, he thought to himself as he glanced at the clock.

“See ya later bro!” hollered Jace as he and his buddies swaggered towards the exit having finished their workout.

“Yeah, later man,” said Zach half-heartedly. Being 6 foot 2 and approaching 250 pounds, Zach was not the type of man most people would pick a fight with and Jace had never given him any trouble but Zach knew that Jace was a total dick to his little brother’s best friend, Ben, and had never had much time for bullies. Zach shook his head as he watched the gaggle of ‘bros’ saunter out of the gym, noting how Jace was the only one amongst them that even looked like he trained despite them all being there for hours each day. There was no denying Jace had a decent physique but in Zach’s opinion it wasn’t deserved, neither Jace nor his friends had any real idea about weight training or nutrition and couldn’t commit themselves to a solid workout plan, whatever Jace had was down to sheer luck and nothing else.

Glancing at the clock again Zach saw that he only had a couple of minutes left and looked around for Matt, his work buddy, who was supposed to be taking over from him. Scanning over the gym floor Zach caught sight of Matt over by the treadmills chatting to one of his many gym crushes.

Hey! Matty…you gonna get your butt over here and start your shift so I can go home or am I gonna have to drag you?” Zach called with a smirk on his face, Matt hated being called ‘Matty’, especially in front of a pretty girl.

“Yeah yeah, I’m comin’,” Matt replied, giving his crush one last wink before heading over to the desk. Matt was slightly shorter than Zach, standing at just under 6 foot, but was just a heavy meaning he looked just a little bigger than Zach in terms of muscularity. “Boom…boom,” Matt exclaimed, throwing up a front double biceps pose as he approached the reception.

“All right, big guy, I think you’ve had your ego stroked enough for one day,” laughed Zach nodding towards the girl Matt had been chatting with a few minutes earlier.

“Gets ’em every time, bro,” Matt winked.

“Yeah yeah, I know,” Zach said, rolling his eyes as he reached under the desk and retrieved his gym bag. “All right then, bro, that’s me finished… see ya tomorrow?” he said as they swapped places behind the desk.

“All right man, catch ya later,” Matt replied, slapping Zach on the back as he did so.

Chuckling to himself at his friend’s typically ‘bro’-ish behaviour, Zach slung his bag over his shoulder and headed for the exit. Leaving the booming music and heavy clang of the weights behind him and stepping out into the car park Zach breathed in deeply. ‘Nothing like fresh air after a day cleaning locker rooms and walking the gym floor’ thought Zach as he walked towards his truck. Catching sight of his reflection in the truck window Zach couldn’t resist an appreciative flex of his bi’s and tri’s before opening the door and throwing his gym bag in the back seat with a satisfied sigh. As he clambered into the truck Zach felt a semi stirring in his shorts. Sexy fucker, even turning yourself on these days, Zach joked with himself. Eager to get the short drive back home over with Zach turned the radio up and took off. As he drove down the long road leading away from the gym he saw Jace still holding court with his buddies, flexing, roughhousing and just generally being obnoxious as they walked home.

“God I’d love to take that fucker down a peg or two…” Zach muttered to himself as he turned the corner and headed towards home, leaving Jace and his cronies behind him. The rest of the journey home flew by as Zach zoned out and listened to the music on the radio only snapping back to attention as he turned onto the driveway of his family home. As he stepped out of his car Zach noticed a set of tyre marks on the driveway, Huh, looks like someone was in a hurry. He shrugged as he strode towards the front door, gym bag in hand. Throwing open the door Zach dumped his gym gear and shoes at the door and headed for the kitchen to grab himself a snack, noting his still half-hard dick bobbing up and down in his shorts. ‘Damn, guess you really do need to blow a load’ Zach thought as he grabbed a protein bar from the cupboard. Having satisfied his hunger pangs Zach wandered through to the living room and flopped onto the sofa.

Figuring his parents were away for a few weeks and he still had a little time before his little bro normally returned home Zach allowed his hand to wander down towards his rapidly stiffening cock and began to massage it through his gym shorts. Letting out a small groan of pleasure Zach yanked his gym shorts off and felt his respectably sized member spring free and slap his lower abs. Zach has always been a ‘shower’ not a ‘grower’ sitting at an impressive 6 inches soft and reaching between 7.5 to 8 inches when hard. Discarding his gym shorts and t-shirt Zach settled himself with one arm behind his head and reached for his eagerly throbbing cock with the other, looking down proudly at his impressively muscled body and smiling before setting to work. As he began to stroke Zach turned his head slightly and took a whiff of his hairy pit, while Zach had always liked girls he considered himself to be ‘hetero-flexible’. There was just something about rugged, masculine men and their musk that got him going. If he was honest, that… ‘interest’ was probably what motivated him to start working out in the first place, he didn’t just admire masculine men he wanted to be one.

After what seemed like an age of stroking, fondling and sniffing Zach felt more turned on than he’d ever been before and yet he was still nowhere near to cumming. ‘What the fuck?’ he thought as he continued to beat his pulsating dick, a thin layer of sweat covering his chiselled body, sniffing the air Zach could smell something…something good. Like a hound tracking a scent, Zach sprang up from his position on the sofa, his impressive 8 incher slick with pre-cum and bobbing eagerly up and down, grabbed his discarded clothes and followed his nose upstairs. With every step Zach’s senses were assaulted afresh, the smell almost overwhelming, as he felt his cock throb harder and harder than he ever thought possible as the smell grew stronger. By the time he reached the top floor his cock was leaking a constant stream of pre-cum, his free hand idly exploring his body in between a few quick tugs of his cock.

“Fuck, what is that?” he moaned aloud, as he followed the intoxicating scent towards his little bro’s room. Knocking on the door Zach called out, “Jack…you in there little bro?”. Receiving no response, Zach retrieved his phone from his gym shorts pocket and texted his little Bro a rapid succession of questions… ‘Where are you? What are you doing? What’s this fucking smell?’ Still no reply. After unsuccessfully trying to call his little bro in between bouts of stroking his leaking cock Zach finally decided he couldn’t take it any longer.

Licking the pre-cum off his hand he reached out and opened the door to his little brother’s room and was hit with what felt like a solid wall of pure testosterone. As soon as the smell hit his nose Zach felt his mind go blank as he stumbled further into his little bro’s room, dick in hand and stroking furiously. It was as though the entire world melted away, and all that existed was his cock and pleasure. Letting out a series of almost primal grunts and groans as he pumped his cock harder and harder, Zach finally couldn’t take it anymore and let out an almighty roar as he shot the biggest and most powerful load of his life all over his little bro’s bedroom floor.

After several minutes Zach began to come back to his senses, though he couldn’t fully shake his hard-on or that intoxicating scent, and stood in shock at what had just happened. Never had he had an orgasm as intense as that, not even during sex, and couldn’t quite believe he’d blown his load in his little bro’s bedroom. Shaking off the daze he unlocked his phone and texted his little bro, ‘You need to call me now’, hit send and began to poke about his bedroom looking for the source of the stink that had driven him into such a sexual frenzy.

Finding nothing in any of the draws or under the bed, Zach turned his attention in the direction of his little bro’s en-suite. Immediately Zach’s attention was drawn to a large gallon jug of… What is that? he thought to himself as the scent began to strengthen once again. Snapping a quick photograph of the mystery container he quickly fired off a message to Jack before setting his phone aside and investigating further. Crouching down Zach stuck his nose into the rim of the container and was instantly floored, once again he felt his rational mind fade and pure, carnal instinct took over as his only just abating boner sprang back to life with added fervour.

Fuuuuckkkk…” growled Zach as his hand once again gripped his meat and began to pump. He knew it was wrong, that something about this situation wasn’t right but it felt so good. Waves of undiluted pleasure washed over him one after another utterly destroying any inhibitions or rational thought he had left and, practically on instinct, Zach reached out and hoisted the gallon jug off the ground and drank more deeply than he ever had before. Within seconds of the mystery liquid hitting his lips Zach’s entire body was reacting, it was as though every nerve ending had been set on fire, an exquisite mixture between excruciating pain and overwhelming pleasure. Zach’s already muscled frame tensing and flexing, his thick pecs bouncing as he chugged from the mystery container, his usually tight abs stretching out to more closely resemble a ‘roid gut as his stomach filled with the contents of the gallon jug.

Somewhere in the back of his mind a small voice was telling Zach to stop, he recognised the taste as cum having sampled his own load many times but he was unable, and unwilling, to put the container down until he’d drained every last drop. As he continued to tip the gallon jug upwards to drain the last of its contents he felt thick streams of cum running down his chin and onto his voluminous chest and abs, his own cock, throbbing harder than even before, had begun to shoot ropes of pre-cum as his senses went into overdrive. As Zach desperately sought out the last few drops of cum from the once full gallon jug his entire body was hit by the most intense spasm he’d ever experienced. Every muscle tensed up at once, his pecs heaving from exertion as he felt his already impressive body begin to grow.

Zach gasped as he felt his arms begin to swell, his skin felt so tight he was worried it would split as his already respectable biceps swelled to the size of cannonballs. Overwhelmed by the sensations washing over his body Zach was forced down onto all fours watching as thick cords of muscle flared on his forearms and staring in disbelief as his hands grew larger, his fingers inching across the carpet. The tightening sensation spread across his shoulders and back as he felt his traps surge in size and the swelling of his lats push his arms away from his sides.

Grunting like some sort of crazed beast, Zach reached for his cock as he felt it surge in size, the tip now resting comfortably on the floor, noticing for the first time how enormous his chest had become as he looked down. Managing to wrap his meaty fist around his still thickening cock Zach began to beat his meat with astounding ferocity, his eyes rolling back in his head as wave after wave of orgasmic pleasure washed over him, saturating the carpet beneath him with his pre-cum.

As he continued to jerk his monstrous member, Zach’s attention was quickly diverted towards his legs, feeling his already substantial quads pushing against one another as they expanded. So powerful was the growth Zach could feel the fabric of his sports socks begin to tear as his feet grew in size and thickness leaving nothing but shreds around them. With every passing moment Zach felt more and more powerful, his entire body buzzing with size and power, each spurt of pre-cum causing his incredible muscle ass to clench.

Just as Zach began to get used to the feelings spreading over his body, the swelling he’d felt spread from his arms, to his back and legs hit his entire body all at one. No longer were individual muscle groups growing in turn, now Zach could feel his entire frame expanding. His muscles growing even fuller to match his increasing height, the intensity of the growth across his entire body pushing him to new levels of ecstasy. Simply unable to control his body any longer Zach’s now mighty cock erupted, spewing the largest, thickest most powerful load Zach could ever imagine.

As rope after rope of hot cum burst from the tip of Zach’s cock, his newly expanded muscle gave way to the pleasure as he slumped down on the sodden floor and rolled onto his back allowing his monumental load to spurt freely up into the air and covering the room in his seed. As the last few shudders of growth eked out Zach’s mind-bending orgasm began to subside leaving him dizzy and disoriented on the floor. Looking down to watch the last few spurts of cum emerge from his cock Zach was lost for words, if not for the towering size of his new member Zach would have seen nothing but the thick mounds of muscle that now adorned his chest. Unable to process what he was seeing Zach relented to the exhaustion caused by his incredible growth spurt and felt his eyes close, comforted by the heat emanating from his sizable cock and the ocean of warm, thick cum that he was laid in.

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Some time later

As his mobile phone rang and buzzed frantically, the newly grown Zach stirred from his unexpected sleep. Groggily opening his eyes to search for the source of the sound Zach once again found his field of vision obscured by his heaving pecs, his newly enlarged traps making it considerably more difficult for him to turn his head, and resigned himself to the fact he would have to rise from his resting spot if he wanted to stop the damned ringing. Raising his arms up in an attempt to rub his eyes Zach once again felt resistance from his own overgrown muscles bulging and fighting one another for space, shocked at the the difficulty he felt when bending his arms and watching as his monstrous biceps flexed.

“What. The. Fuck,” Zach grumbled, his voice deeper than he remembered. Though generally aware of his transformation the details of his changes eluded Zach. The sheer overwhelming force with which both the physical and emotional sensations had hit him had clouded not only his judgement, hence his current predicament, but also his memory.

“This can’t be fucking happening…” Zach rumbled in disbelief as he hefted his now considerably larger body upright into what turned out to be a deeply uncomfortable sitting position. Zach stared down at himself, a living breathing mound of muscles, as he felt the thick layer of pre and cum coating his back begin to run down. With a not inconsiderable amount of effort, Zach managed to heave himself up off the floor, with the assistance of the nearby furniture, and immediately banged his head on the light fixture above. Swatting the light away Zach continued to rise to his full height, standing at well over 7 feet tall, and surveyed the scene below him with astonishment. The entire room, his little bro’s room, was drenched with his load. His socks lay in tatters on the floor, shredded by the expansion of his now monstrous feet. The furniture around him cracked and damaged both during his transformation and by supporting his tremendous bulk as he attempted to stand up. Most of all, however, Zach couldn’t believe how fucking huge his body was.

Staring down at himself Zach could see little more than his basketball sized pecs and the tip of his half-hard cock bobbing up and down, feeling that unusual resistance from his engorged traps as he turned his head he stared in amazement at the size of his swollen arms. His newly transformed biceps were easily the same size, if not larger, as his quads had been before the growth spurt and his forearms were bigger than most guys legs. Feeling his cock begin to stiffen as he admired his freakishly large muscles Zach lumbered over to the en-suite, struggling to fit himself through the frankly child-sized door frame, in search of his little bro’s full length mirror in order to see if his legs were as monstrous as the rest of him. Luckily for Zach he could see and feel perfectly well how large his upper body had become without the aid of a mirror because the view he managed to achieve of himself in his little bro’s mirror barely reached his pecs. As he’d lumbered to the en-suite Zach had noted his gait had changed radically since his growth spurt and looking in the mirror it was not difficult to see why. His lower half was freakishly large and far beyond anything ever seen on a human being before, in fairness that was true of the rest of his body as well.

Before Zach could even begin to examine his quads his jaw dropped at the sight of his cock and balls. Easily over a foot long and thicker than most men’s forearms, the semi-hard cock rested comfortably on top of the most enormous set of balls Zach has ever seen. Reaching down to grope his package, again feeling that unfamiliar sensation of his muscles competing for space, Zach guessed that each of his nuts were bigger than baseballs. Between the sight of his gloriously swollen frame in the mirror and the satisfyingly weighty feeling of his engorged package resting in his hands it was all Zach could do not to blow his load right then and there.

Pulling his monolithic equipment to the side Zach’s eyes lit up at the sight of his quads. Easily wider than an average guy’s torso his quads had grown so mind-bendingly large he couldn’t see both of them in the mirror at the same time. As his gaze continued to shift downwards he noted how widely set his stance was in order to accommodate his tree-trunk quads but the sight of his calves was too much for him to bear. Zach felt his cock spring to attention once again as his eyes soaked in the sight of his impossibly large calves. His calves were so large he needn’t have bothered turning around to view them, their immense size was clearly observable from the front, but the true freakishness of their size, rivalling the size of many successful bodybuilder’s arms, was revealed to him as Zach flexed them both in turn. By this point Zach could feel his rational mind begin to recede once more as he felt his cock surge sending a wave of pleasure through his body causing his enormous glutes to swell and tighten.

As Zach’s eyes continued to roam over his incredible body his cock was once again leaking unnatural amounts of pre-cum. Each flex of his muscles sent another jolt of pleasure through his body as he felt the power surge through them, bulging hard, taking note of the insane level of definition and vascularity he now had. His body was a veritable roadmap of veins, muscle and sinew, barely a hint of body fat remained as he began to run his thick, brutish hands over his body. Losing himself in self-worship Zach once again found himself stroking his oversized cock, relishing the sight and sensation of each of his muscles tensing and bulging across his frame until he finally unleashed another sizable load all over the now, by comparison, tiny en-suite. Giving himself one last appreciative look up and down in the mirror, his body glistening with sweat and cum, Zach grinned wildly as he turned back towards the bedroom where his phone was once again buzzing.

As he walked back over the bed to retrieve his phone Zach made a point to soak in every little change his new body made to the way he walked and moved. The characteristic waddle of a man so muscled that his quads simply don’t allow him to walk normally, the swing of his monster cock and the slaps it made on his quads, having to duck and twist himself through doorways, the restricted range of motion in his arms due to the sheer size of his musculature…his mind was abuzz with pleasure. I fuckin’ love this, Zach thought to himself letting out a loud hhmmmmphhh as he bent over to pick up his phone. With considerable difficulty Zach managed to use his now much too large fingers to type in his passcode and unlock his phone as a wave of messages and missed calls popped up.

“Damn little bro, guess you do know what was in that gallon jug,” Zach chuckled, enjoying the new, deeper timbre of his voice. Opening the speech-to-text application on his phone Zach set about replying to his little brother.

‘Hey little bro where are ya? Sorry I missed your messages, I did a little investigating and then took a nap. I’m feeling much better now.’ Zach dictated to his phone, figuring he’d leave his incredible transformation as a little, or big, surprise for his little bro. After all, neither words nor pictures could do his size justice…particularly as he’d never fit in the frame.

Jack’s response was swift. ‘Zach! We’re at the cabin, do not go near that gallon jug without putting a stopper in it or something…just seal it up and drive down here, please’

Zach chuckled to himself, ‘Bit late for that little bro’ he thought before replying to Jack’s message assuring him he’d bring the gallon of cum to the cabin just as soon as he’d had a shower and a change of clothes. With that Zach tossed his phone onto the bed and headed for the shower, keen to hit the road and show off his new body. Still not accustomed to his new size, Zach didn’t realise just how difficult it would be to take a shower as a more than 7 foot tall, 350-pound monster. Rather than being discouraged or frustrated Zach revelled in his enormous size as he soaped his monstrous frame up as best he could before crouching down beneath the shower head to rinse off, fighting the urge to indulge in yet another epic jerk off session. Satisfied that he’d washed the bulk of the sweat and cum from his body, and not too upset at the lingering stink of musk and sex he couldn’t seem to wash away, Zach shut off the water and lumbered out of the shower, side-stepping the larger pools of cum laying atop his little bro’s saturated bedroom carpet, and headed towards his own room in a likely futile attempt to find some clothes.

Entering his own relatively tidy room Zach couldn’t help but feel a little guilty at the mess he’d left across the hall in his brother’s room. Glancing around at the clothes in his wardrobe Zach sighed. Well… this should be interesting. Reaching for the largest oversized hoodie he owned Zach struggled to yank it down past his head only managing to get the damned thing past his shoulders after around ten minutes of wriggling and pulling. As he finally got the hoodie down past his shoulders he felt the seams along the arm split as he attempted to stuff his overblown bi’s and tri’s into the sleeves. Figuring he could pull off the sleeveless look Zach persisted with the other arm allowing himself a small sense of satisfaction that his arms were now literally too massive to be contained. As he pulled the hoodie down over his vast torso he hear a loud tear as the front of the hoodie split from the collar to about a quarter of the way down as it attempted to contain his mountainous pecs.

Fuuuck…” Zach groaned, though he wasn’t too annoyed at the way the tear showed off his chest, noting that the once oversized hoodie was basically skin tight and fit more like a crop top than anything else. Turning towards his drawers, Zach pulled out the biggest, stretchiest pair of shorts he owned before reaching down to attempt to pull them over his herculean calves, quads and ass. No sooner than Zach had bent over, the hoodie he’d just managed to get on tore from top to bottom exposing his incredibly dense back.

“Fuck it,” Zack mumbled as he tore the remaining scraps of the hoodie from his torso and threw it away in frustration before returning his attention to working his shorts up his massive legs. Compared to the hoodie, the stretchy fabric of the shorts presented little challenge up until the waistband had passed his quads at which point the seams along the legs began to tear a little as Zach positioned the waistband as close to his waistline as possible. Turning to his mirror Zach looked at the incredible display he was putting on, the once baggy and long shorts were clinging to every striation in his massive quads and ass, the waistband barely making it to his waistline made them look more like short shorts and his bulge was frankly obscene with the base of his shaft peeking out the top of the shorts and the head of his cock poking out the bottom. Sighing to himself as he figured this was the best he was going to manage, Zach turned and waddled out of his room, collected his phone from his little bro’s bed and continued to waddle down the stairs, his now much larger feet overhanging each step. Deciding that the world was going to have to see him eventually, Zach wasted little time in swinging the door open and lumbering down the drive to his truck and clambered in, barely squeezing himself into the driver’s seat even with the seat pushed all the way back and reclined. As he lowered himself into the seat he felt the back of his shorts give way, removing the last scrap of modesty he had left.

“Ah shit…” Zach sighed, as he forced the truck door shut and took off for his little bro’s cabin.

5 parts 18k words Added Apr 2022 Updated 10 Sep 2022 33k views (#288) 4.8 stars (42 votes)

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