SNU-5|VU

by DracumSum

Nathan and Nick have to complete a biochem project on the metahumans caused by the failed SNU-5 nanobot project—only they don’t know any, and the brief random encounter Nathan had at a bus stop the other day won’t help them. Or will it?

SNU-5|VU (Survival Nanobot Umbrella—5 subgroup Violence/Utility) was a military funded biological enhancement protocol designed as a nanite based response to the large number of bipedal armored vehicles (popularly known as mechs). The primary goal of the program were to produce humans that could feasibly go toe to toe with a mech. It was an abject failure. Field testing showed that the enhanced soldiers consumed far more under combat conditions than could easily be supplied, their system could not deliver enough oxygen to allow them to retain their previous muscle memory, and trying to adapt existing weapons simply by scaling them up failed. Needing to retrain years or decades of learned skill and launching a weapons development program for every small arm, as well as developing the supply chains to get those to the front, undermined the underlying intent of the program, namely to produce mech capabilities without mech development costs.

A secondary problem was that the nanobots needed to remain active in the subject, in order to continue maintaining the subject’s metabolism and structural integrity. This meant that enemy theft was always a worry, and that nearby soldiers could be unintentionally infected by the nanites, since they could spread through bodily fluids.

…

Nathan groaned as he looked into the night, rain pouring down outside. It was a couple minutes’ walk to the bus stop, then a significant wait, without a shelter. After a few moments, he grimaced, and headed out into the storm, trying to think about schoolwork rather than his already sodden clothing.

All right, need to get that calc project done… then biochem…. he thought to himself, before the rain soaked his shirt and sent a shiver down his spine. He shook his head and continued planning, eyes fixed on the lamppost seemingly forever away. Making it to the post, he stood there, trying to keep himself occupied.

“You can stand underneath my jacket,” a rumbling voice said from far above. Nathan jumped and looked around. Big enough to blend into the background was a… well, no other way to describe them, a giant. Nearly 20 feet tall, they were wearing a dark rain jacket, one that matched the surrounding woods a little too well. Millie could see their bare feet, huge enough not to compress the ground too much, leading up powerful legs to… well, the shadows concealed the rest.

“Erm… thanks!” Nathan said, flushing at the offer and his embarrassment at completely missing one of the few metahumans on campus. He darted underneath, and sighed as the rain stopped. “Seriously, thank you.”

The dark cavern was a warm and humid, smelling strongly of the giant. Maybe a little body odor, but at that size, they were almost constantly sweating, trying to get rid of excess heat from their overactive metabolism.

The giant chuckled. “No problem,” their voice boomed, surrounding Nathan. They shuffled a bit, their foot tapping Nathan and figuring out where he was, and the constant rain on the massive amount of clothing kept the rustling of fabric on fabric going. Nathan looked over his soaked form a bit distastefully. His black shirt and shaggy brown hair were absolutely soaked through, and they both stuck to his body like a wet poodle. He spent a few minutes trying to fix them a bit, but gave up, deciding to deal with it in his apartment.

The rustling kept going, longer than Nathan would have expected, and he could hear the giant’s breathing deepening.

He looked up at them concerned, but there was no explanation, maybe just a hint of movement, then a gasp, and Nathan was coated in a strong smelling liquid. He froze, eyes and mouth wide open in shock, as it started to drip down his skin. The giant froze, the rustling stopping for the first time, then backed away, before starting to run.

Nathan looked at their disappearing form in astonishment, then shook his head. His hair slapped into his mouth, and he grimaced at the taste.

“What the hell was that about?” he wondered aloud, as he finally saw the bus coming into view.

…

Signs and symptoms: Upon initial exposure to the nanites, they will undergo replication until they reach a critical mass, targeting the endocrine system, altering the metabolism, and encouraging strengthening of the ligaments and tendons, attempting to prepare the body for significant growth.

During this incubation period, it is possible to deactivate the nanites without negative effects upon the subject.

…

About a week later, Nathan was at the gym, enjoying one of the few perks of being a student and blowing off steam. “Can you believe what they’re expecting us to do? That biochem project will take a week to get done right.”

“What’s it on?” his boyfriend, Nick, asked walking next to him on the treadmill.

“Metahumans. SNU-5 variant for whatever reason. Like I give a crap about failed military projects. It’s not even that impressive, just the first one to get out of the lab and into the general population. And that’s after I scared off the only one nearby.”

“Oh, the bus incident? You worried that you got infected?”

“No, infection is relatively difficult. It’s only spread through blood to blood contact or sex, and it’s not like I could even reach that high. Seriously, they would have needed to pick me up and use me as a dildo.”

Nick stumbled a bit, surprised at Nathan. Wasn’t like him to talk about sex in public. Or private for that matter.

Nathan kept talking. “Or bukkake me? I doubt that the men can do much with normals, and if their cum shots increase… well, by volume they’re something like twelve times normal men, so… I’d guess that per ejaculation? But the hormones also tend to stimulate sexual characteristics… Let’s say they cum the same amount as one of those things on your phone. Haven’t seen anything in my textbooks. Would have made those more interesting.”

Nick was beet red. “You feeling all right?” he asked.

Nathan smirked at him. “Yes, and I can tell you are feeling great.” The smirk shifted into a leer, as Nick realized that he was tenting. He tried to reposition himself, as Nathan laughed huskily. “Is that what turns you on? The thought of me getting covered in jizz? Or being used as a dildo for a giant woman?”

“Or a giant man,” Nick said, without thinking. then shook his head, and tried to wrap his mind around the situation. “One of many things, yes. And, now, I know you like getting hot and bothered in public.” He grinned as he noticed a matching tent.

His boyfriend laughed, and they spent the rest of the walk chatting, getting increasingly explicit. Most of two miles later, Nick looked at his phone, and made an unhappy noise. “Erm, I need to get home and get some work done. I’ll text you later,” he said, sliding off the treadmill and dashing out of the cardio room.

Nathan watched him go, still feeling energized. For all his complaining, he still had a while to work on his projects, and he’d had so much energy recently. He was sure that he’d lost a little weight too. Idly, he pulled up an introductory workout plan on his phone. For some reason, he really felt like lifting some heavy shit.

…

Once critical mass is attained, substantial growth will begin. The subject will become ravenous, followed by lethargic. They will rapidly grow towards the upper limits of human potential over the next 48 hours. Frequent full body spasms will occur, stimulating connective tissues and reducing the incidence of torn muscles.

…

Nathan had been scaring Nick a bit over the last week. Every time they’d seen each other, Nathan had been working out or eating. He couldn’t disagree that it was working for him, his clothing had become looser around the belly, and tighter around the arms and ass, but… it shouldn’t be this quickly. It should have been weeks of dedicated training and dieting to make those gains. Maybe he’d gotten some designer cosmetic hormones or something. They were pretty outrageously expensive, but not that uncommon. Hell, the entire high school football team had gotten disqualified for basically mutating themselves into bulls with overdosing. Was pretty funny when they’d had to stop and most of them had grown massive boobs and udders.

Still, Nathan said he’d meet Nick in the dining hall, so Nick was heading there now. He pushed his way through the double doors and looked around. He thought he saw Nathan’s favorite shirt, and started heading over towards it, then froze, gaping.

He’d claimed an entire table to himself, and it was loaded with half empty plates. He was eating, almost frantically, and managed to wave at Nick. He walked over, concerned. “You feeling all right?”

“Yeah, never better. Just finished a half marathon, a couple hours swimming, and a lift.” Nathan said proudly, pausing from eating for a moment, then his nostrils flared and he turned back to the food.

“What the fuck? Why aren’t you dead?” Nick managed, and got a shrug in return.

“I’ll go to the hospital after this, if you get me more food?” he offered. Nick rolled his eyes and sighed, but nodded. There was no way to make Nathan do something he didn’t want to do. He headed off towards the buffet line, and swiped his card, then started loading up on all of Nathan’s favorites, heavy on the carbs, fats, and proteins. Then he paused and called the hospital.

“Hello, State Tech Medical nurse’s line speaking,” a cool feminine voice on the other end said.

“Hey, my boyfriend has eaten a table’s worth of food, after doing an iron man. And he didn’t really start to exercise until last week.”

The woman on the other end clicked his tongue in thought. “Sounds like some hormonal overdose. He seem in any immediate danger?”

“I… don’t think so?”

“All right, you’re at the dining hall presumably?”

“That’s right.”

“Okay, we have a few EMTs in the area. I’ll ask one to head over and check him out. We’ll send an ambulance if anything’s wrong.”

“Erm… thanks! You do this a lot?”

“Fairly often. Biggest difference is that it isn’t someone who passed out because they got their first erection after the hormones took.”

Nick laughed, then stopped when the receptionist didn’t. “Well, thanks for all your help. Hope I don’t need to see you soon.”

“Good luck with your boyfriend.”

Nick hurried back to the table, putting the food within reach, and starting to eat his own. Nathan excitedly went for the plates, gulping it down as fast as he could. Twenty minutes later, a blue suited EMT walked through the doors and looked around, then headed over to the eating couple. She stared at the pile of plates for a few seconds.

“You still hungry?” She asked Nathan. Nathan nodded, looking pleadingly at Nick. Nick sighed and got up, heading for the line again.

When he’d gotten back, the EMT was on the phone. “Yeah, looks he’s eaten enough food for a couple weeks. His stomach is visibly distended. If it’s just from this meal, looks like something big’s about to happen, which probably means something not hormone related.” She listened for a few moments. “Yeah, that’s what I thought. Has Sarah said anything? Nope? All right then. We’ll put it down to chance infection and try to get him under observation. Get some food ready for him.” She hung up her phone and looked at Nathan.

“All right, we think you might have been infected by something. Would you mind coming with us to the hospital? We’ll have more food ready,” the EMT promised. Nathan had started slowing down, looking increasingly tired, but managed to nod.

“Yeah… I… how much did I eat?” he asked, looking around, then down at his stomach. It looked like he was carrying triplets. “That’s…. not good…” he said.

“Can you walk?” the EMT asked, approaching Nathan and putting her own arm out, letting Nathan grab on. Nathan nodded and slowly got up. The three shuffled for the door, Nathan leaning on the other two as he started to collapse. The EMT put her shoulder underneath Nathan’s armpit, taking most of his weight, as Nick did the same on the other side.

They managed to get out to the curb and they sat down. A few minutes later, an ambulance pulled up, and two more EMTs put Nathan onto a stretcher, then loaded him in. He was totally passed out, motionless aside from occasional muscle spasms, running from foot to head.

“You his relative?”

“Boyfriend.”

“You know how to get to the hospital?”

Nick nodded. “Bus will be here in 20 minutes.”

“Yep. Don’t think he’ll need surgery, but he’d probably appreciate you being there for him.”

A couple hours later, Nathan stirred, groaning as he blinked his way awake.

Nick was sitting by the hospital bed, doing homework on his laptop, which he hurriedly closed as he heard Nathan move. “Hey, how are you feeling?” he asked, eyes full of concern.

“Sore… full,” he managed. “Water?” Nick hurried over to the sink and got him a glass. “What’s wrong with me?”

“SNU-5… they think you’re going through stage 2… so you’ll be in and out of consciousness for the next few days. I think you’ve already grown an inch.”

“Damn… SNU-5? I wonder if… that’ll count for the project?” he asked, then started drinking, splashing most of it over his front.

“Hey, careful with that. It’ll be here when you need it,” he said when he finished, refilling it and putting the cup on the bedside table.

“Thanks… I… yeah… we’ll… have a lot to talk about,” he managed, eyes already closing again.

Nick nodded, and watched him go back to sleep. He sat back down, as he slept, multiple IVs keeping his body full of the nutrients it would need as he kept growing, muscles twitching as they grew too.

When Nick woke up the next morning, Nathan’s stomach had largely shrunk back down, the huge quantity of food being burnt to help his body grow at the insane pace it was. Numerous empty IV bags were on stands, left there by the nurses trying to make sure that they could keep track of everything that had been pumped into his body.

He could tell that his shoulders were significantly broader, his arms longer, muscle more defined. Most of the pudge around his face and neck had disappeared, burnt to provide calories. He wasn’t sure because of the blanket, but he had to be most of a foot taller, definitely taller than he was.

He blushed as he felt a familiar hardness at the thought, but couldn’t tear his gaze away as he continued down Nathan’s body, appreciating every new inch and change.

After a few minutes of staring, Nick finally managed to pull himself together enough to realize that he needed to use the bathroom, and that he really needed to head to class. He ripped out a piece of paper and left it on the table, saying he’d be back afterwards.

By the time Nathan was ready to be discharged, he was head and chest taller than Nick, nearly all fat burned off his body by the extreme strain, and he looked absolutely exhausted. He was only wearing an extra-long patient’s gown, which reached partway down his thigh, and Nick couldn’t help but stare around his crotch, and his feet, which had grown even larger to support his much greater weight.

“All right, you’re going to need to eat a… frankly stupid amount. You’re only a bit more than a third of your final height. At least probably. There’s some variation, but you’ll definitely need to keep enough fat to keep the nanobots happy. Go to the pharmacy on your way out, there’s a lot of supplements you’ll be taking to prep for the next two phases. And don’t be too surprised by any urges. Your hormones will be going wild, and a lot of built in blocks have been removed. We’ve given your boyfriend some hormone pills to take if you find he can’t keep up,” the doctor that had been supervising Nathan said as he prepared the proto-giant for discharge. “We’ll see you in about a week for a followup check on your nanobot levels. We can figure out whether or not you’ll need to stay here for observation at that point.”

Nathan nodded, looking a bit embarrassed. “What about clothes?” he asked after a moment.

Nick perked up and pulled out a pair of sweats and a large shirt from his bag. “I have some stuff here. I wasn’t sure how big you were, so I just went oversized. We can get more stuff when you get home.”

“Oh, and you should drink at least four of these a day,” the doctor said, putting a large protein shake into Nathan’s hand.

Nathan looked around his apartment, still getting used to his new size. He could reach up and put his palms flat against the ceiling, and the fridge seemed… far too small. The counters were filled with protein powder containers and premade protein shakes that Nick had been transporting back from the hospital, for when he got hungry between meals.

He walked into his bedroom and stripped out of his clothes, looking at herself in the mirror. He… was very thin. Not enough time for his body to actually fill out, and he could see each muscle clearly, but skinny strong, not real strong. Not yet. That would come later, after the next stage. Still, his shoulders gave him a nice V shape, and his legs had promise. He couldn’t deny he wasn’t looking forward to this a bit, especially after staring at SNU-5s for the last couple weeks for his research…

He took a long drink of the shake, and sat down, the mattress practically collapsing underneath his weight. Then looked at one of his old shirts. It was… tiny. Kid sized. For someone a foot shorter and with shoulders two feet thinner. But he didn’t have much muscle mass…. He shrugged it on, the fabric around the neck splitting as he forced it over. It used to cover him easily, reaching past his hips. Now… it was a belly shirt, if it had been a bit more comfortable. He smiled to himself, made a stupid muscle pose, and froze as the shirt ripped along his back. Fuck… he didn’t look it, but there was a lot of strength in his body. Nathan took another sip of shake, and started getting dressed in the clothes Nick had picked out. They weren’t complementing, but… they’d probably only last a week anyway.

…

When patient reaches 2.5 meters, the nanobots will being to optimize the body for further growth. Medical attention will be necessary to supply the body with sufficient materials to prevent severe harm as the nanobots carry out their programming from this point forward. Growth will halt temporarily as the nanobots replicate in preparation of the next phase, and hormone production is increased.

…

Nathan and Nick were at the dining hall again. Nathan had filled out a bit, his nanobot boosted metabolism adding pounds of muscle and fat to his frame a day, as he spent his time eating and working out, entirely at the doctor’s orders. Nick was largely in awe of him, and delighted in getting his boyfriend more food, water, protein shakes, and… relief.

The changes had spurred a significant boost in all his systems, and being cornered by his towering boyfriend, eyes level with his growing pecs, distracted by his increasingly defined abs, seeing his horny grin, watching his bulge gradually approach cucumber smuggling, was becoming a daily occurrence. Definitely something he longed for and lusted over… He finished another plate and caught his eye, then slowly got up, the table groaning as it slowly stopped straining underneath his massive frame. He started walking off to the bathroom, his pants tight against his defined ass and thighs. He looked back over one shoulder, eyes glinting as they invited Nick along for the ride.

Nick’s cheeks flushed red, and he dropped his fork and knife, cock springing to attention as he followed at a hopefully discrete distance.

A few moments later, he opened the door to a nearby janitorial closet, and a massive hand clamped around his waist, nearly lifting him up in the owner’s eagerness to get at the goods underneath. Moments later, he was naked, blushing, looking up at Nathan.

As much as Nick enjoyed having sex with his boyfriend, and he could still take his cock, there was something about being used by the increasingly massive giant, hugging and licking the wrist thick length dripping pre in front of him. Or, if Nathan was feeling like bottoming, gently taking his arm and using him as nothing more than a toy for his own enjoyment, fisting his asshole.

The biggest change had been around Nathan’s crotch. Aside from merely thickening, the cock had become disproportionately massive and slowly approaching inhuman. It had darkened, fingerthick veins running along the sides, and the foreskin regrowing. The cockhead had become more prominent, flatter, with a ridge that rammed against Nick’s prostate perfectly. Soft, it was clearly outlined through his compression shorts and pants, trying to keep it under control. Hard… it became a heavy spire, sticking straight out from his crotch, demanding attention. His balls had grown as well, pumping massive amounts of testosterone into his system, helping explain the cut abs and thighs that framed his new virility. They were sensitive and massive, forcing his legs apart when he sat down, nearly the size of oranges… Pre nearly constantly dripped from his cock, almost making it self-lubricating, and it released a heady musk that left Nick hard and eager to please. Most of his body hair had fallen out, leaving it everything, while his hormones left him almost always ready.

Nathan gently grabbed Nick by the shoulder and pulled him gently but inexorably closer, his cock’s drip of pre slowly becoming a stream as he slowly started playing with his shaft. Nick’s knuckles started tracing his asshole, teasing them apart as Nathan’s cock hardened, becoming darker skin becoming redder, slowly filling Nate’s world. Nathan’s smile took on a predatory glint, and he started pulling Nick’s head in to suck on the sensitive spire, as Nick’s fist started pumping in and out, the muscles in Nathan’s ass forcing Nick’s hand against a prominent ring shaped organ, his other hand starting to stroke his own length. He could feel Nathan’s tightness slowly give way, as his constant low level of arousal built and he coated Nick’s face in his fluids, his scent filling the room.

Nathan started grinding against him, pressing down against his invading arm, playing with his cock and nipples, gasping in time with his sucking. It wasn’t going to take long, he’d been on a hair trigger all week, and he needed to head to the hospital soon anyway, for the next stage, but for now, he fucked his boyfriend with all his might, his muscles, his size, and his overwhelming need.

Nick sensed that he was getting close, the rhythmic tension in his ass was getting stronger and less consistent, as he started to lose control. He sucked harder, pumped faster, and braced his legs as Nathan started bouncing, the floor complaining as he really got into it. A few moments later, he went rigid, hand over his mouth as he bit back a cry, and Nick was blasted by a stream of cum, stream after stream coating Nick’s face and chest. He blinked a bit lazily, enjoying how much pleasure he gave his boyfriend, and the heady musk that left his head spinning.

Nathan knelt down and hugged him gently. “I can’t wait to use your entire leg…” he murmured into his ear, and Nick’s cock jumped at the image.

…

From 2.5 meters to 3 meters is, surprisingly, the period with the highest incidence of injury and negative outcomes. The nanobots are conducting the greatest changes, coating then replacing the bones with a carbon fibre-like material, improving the capabilities of the nerves, and altering the metabolism to function at a significantly greater size. If any of these do not occur properly, medical intervention becomes necessary.

…

Nick was waiting outside the hospital for Nathan. He’d been off limits for the last few days, something about how he couldn’t afford any unregulated changes in hormone levels, so he’d been helping move his stuff to his new dorm room. The administration had finally agreed that he was too big for the regular one, after his legs and knees dangled off the end of the bed and he could press his head against the ceiling if he went onto tip toes.

Now that he was half a meter taller, they’d finally managed to get a specialized living area ready for him, with oversized… well, everything. Higher ceilings, larger light fixtures, special keyboards, closets, toiletries, and everything else. The only thing he wasn’t mostly satisfied with was the clothing. Baggy sweats and t-shirts, but they couldn’t do much better until he reached his final size. He’d left a pair with the nurses, and they’d told him he would be ready soon but…

His jaw dropped as Nathan managed to squeeze his way out of the front door. He saw him gaping, and blushed, covering his face a bit. It might have been meant to hide, but with his new body, it just accentuated his form. He’d filled out, going from strong but stick-like to Greek statue, his arms straining his shirt, his pecs and abs clearly outlined, and his pants tight against his hips and ass. Then Nathan turned back towards Nick and the Greek Statue was completely blown away by the knee length python snaking down one leg, while the overstuffed crotch hinted at more growth.

He smiled at Nick’s reaction and started jogging towards him, his disproportionately large feet leaving clear outlines in the grass and dirt, though not much deeper than Nick himself would have.

“You… you look amazing!” Nick managed, running a hand along his rock hard thigh, head even with his belly button.

He knelt down to him, until they were looking each other in the eyes. “And I’m going to keep getting even bigger. I’m only half grown.” His massive hand, big enough to palm his head, gently wrapped most of the way around his thigh, one finger playing with his tent.

Nick groaned at the image, excited to keep helping his boyfriend.

…

From 3 meters to 6 meters, the new SNU-5|VU continues to grow at a rate of nearly a meter a month, gaining several tonnes of mass, their hormonal profile pushing them towards the intended combat role by promoting muscle growth and increasing sex hormones. Various primary and secondary sexual characteristics may be enhanced as a result. Aggression and sexual domination are also common.

…

Nick sat in the middle of Nathan’s bed, about a quarter the size of a tennis court. Nathan’d finally stopped growing, and was planning a long night to enjoy his new size with his boyfriend in celebration. Nick was less than a third of his height, barely coming up to his knees, and was acutely aware of that difference. They’d been spending more time apart recently, he’d been trying to catch up on schoolwork and he’d been… well, it was hard to compare the minor definition he’d gained to what had happened to him. He shook his head, focusing on the present. He heard a knock, and practically jumped up, eyes fixated on the door.

Nathan stepped through, quiet on the polished concrete floor, and smiled down at him. He was huge, over 6 meters tall, multiple times his own height, large enough that people missed him because their brains were programmed to think he was a tree or building or something. His bare feet padded softly towards him, slowly removing his rain slicker, exposing the perfection underneath.

It was difficult for Nick to really wrap his head around it, no matter how many times he went to sleep between the valley formed by his pecs and prominent nipples, massaged his feet, taller than himself, or tried to wrestle with individual muscles stronger than his entire body. His form was designed to go one on one with tanks and mechs, against him, even playfully, he dominated him in every way.

And he couldn’t deny how much he loved it.

His built form, still wearing the cheap clothes while he ordered stuff more appropriate to his final shape, bulged and curved perfectly, the t-shirt pulled taut against cut abs, stretching across hill like chest, with hard nipples bigger than Nick’s fists. Further down, his V shape was exaggerated, and he delighted in it with low cut pants that showed off his Adonis belt.

Nathan paused, enjoying Nick’s near worship, and ran his hands up his body, cupping his bulge, showing off his stomach, and finishing on his chest. “You want to see more?” he asked, a hint of a smile playing around his mouth. Nick nodded, mouth dry, cock tenting his pants.

He grabbed his top and strained for a moment, easily ripping it in two, as his arms strained the sleeves, stretching it and causing the cotton to crack in protest. He grabbed his pants and did the same, his improved skin, muscles, and bones easily overpowering the millions of threads. He stood before Nick, naked and loving it. He was still soft, knee length cock, longer than Nick was tall, slowly beginning to drip, his scent already beginning to fill the huge space and he sauntered over to the massive bed, slowly lowering himself next to his little mountain climber.

Nick was achingly hard, but stayed clothed, Nathan liked playing dress up with him. He leaned back, trying not to roll into his boyfriend’s depression in the bed, but started sliding, as he spread his legs. Nathan started playing with himself, fingers nearly as long and thick as Nick’s arms spreading his asshole, and Nick clambered onto his toned stomach, then started crawling towards his hill-like cock. It’d kept changing, becoming textured as nubs had grown around the head, a ring had developed in the middle, and the veins had grown to wrist thickness, everything dwarfing anything Nick chose to compare. Nathan chuckled, the vibrations running down his body and causing him to shake.

“Let’s get you into something more comfortable,” he murmured, his massive size meaning Nick could still hear him easily, as his hands reached for him, helping him pull his clothes off. He frantically unzipped and unbuttoned his pants, as he began to gently tug. It was difficult for someone of his strength to tell the difference between gentle and clothes ripping, and he barely managed to pull them off enough that they slipped away, turning dark with the pre slowly dripping onto and around Nick.

Finally, he was naked, laying there on Nathan’s lower abs, gasping in excitement as the giant’s hands started playing with him. He hugged a finger tightly, and shuddered as another stroked against his erect cock. Nathan gently let him go, and pulled his balls out of the way, as his other hand started playing with his chest, pinching his nipples as the smell of arousal thickened and pervaded Nick’s entire world.

Nick reached Nathan’s fork, and slowly lowered himself to the ground, finally able to look up at his much larger lover. He gazed back, a mixture of love, adoration, and naked lust in his eyes, as his huge erect cock promised a long, wet, enjoyable night. Nick was sure his expression promised the same, and looked down.

His asshole had changed as well, puffing out and becoming much more sensitive, as his prostate had continued to swell and become more sensitive, bulging out in a massive U, surrounding his rear tunnel. Still, it was his balls and cock that had changed the most, swelling and lengthening to nearly taller than Nick himself, and oblong yoga balls, practically twitching and vibrating with sheer virility. Nathan ran his hands through his stream of pre, directing it down towards Nick, helping him lube up, and the sensation across his new glans sent a tremor through him and the bed. Nick made sure that both arms were properly lubed up, then slowly started pressing into the soft asshole in front of him, both arms rapidly finding the hypersensitive oversized prostate within. Nathan twitched, his cock spurting a blast of cloudy liquid, and he relaxed into the bed.

“Oh, fuck… you can play me like an instrument,” he moaned, his muscles tightening, then starting to undulate, gently contracting around the invader, pressing against Nick.

Nick grinned and began thrusting most of his body in and out, his cock rubbing against his boyfriend’s entrance, mouth lapping up every bit of musk he could.

Nathan was still on a hair trigger, and rapidly shivered with a small orgasm, splashing Nick’s front and top, the first of many to come.

By the end of the night, Nick and Nathan were both exhausted, covered in fluids, and cuddling together, Nick nestled on Nathan’s chest.

“That was amazing.” Nathan gasped, pressing his arms to his side and enveloping Nick for a few seconds. Nick relaxed in his warm grip, and Nathan let him go before he started to gasp for air.

“I’m glad you thought so.” Nick said. “Tasted different tonight,” he said, licking his cum slick chest. “Bit harsher than usual.” He chuckled, and Nathan froze underneath him.

“What’s wrong?” he asked, looking up at him confused.

He paused, as if weighing something. Then looked down at him, a smile playing around his lips. “Well… how do you feel now that you’re infected by SNU-5? I’m sure that my advisor would love a repeated trial.”

Nick stiffened on his chest, then relaxed. Well, one part remained stiff. “I think I’d love that,” he said.

Need to say thanks to xkcd’s What-Ifs for giving me a rough idea on the scales actually employed here. Volume will never not break my brain.

Requested by blackusurp.

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Rapeenzel by Ziel Ziel got to thinking about old fairy tales and thought, “You know what these stories need? More gay sex and macro-dongs!” So he threw in a touch of cutesy fluff and some soft CV elements. Lots of sappy romance and monstrous dongs ensued. 6,583 words Added Sep 2015 25k views 5.0 stars (8 votes) •Cock Growth•Cock Vore•Huge Balls•Huge Cock•Hyper Cock•Prehensile Cock•Hyper Cum•Always Shirtless•Medieval(ish) •M/M

The salt: the African-American by RdyRoger 3 parts 3,969 words Added Jun 2010 14k views 5.0 stars (2 votes) •Cock Growth•Huge Cock•Muscle Growth•Muscle/Strength•Increased Libido•Voice Deepening•Size Increase•Race/Ethnicity Change•Hair Growth/Getting Hairy•Hairless•Tongue Growth•Nonconsensual change

Small problems by The Obsessive-Compulsive College freshman Curt has certain inadequacies he’d like to correct. (Hint: Remember the “Better Living through Chemistry” meme?) 7 parts 9,668 words Added Sep 2009 37k views 5.0 stars (9 votes) •Cock Growth•Huge Balls•Huge Cock•Hyper Cock•Hyper Cum•Increased Libido

Summer breeze by Dave Swim hunk Mike is asked to employ his recently improved body and unstoppable libido in the service of intergalactic peace. 5,170 words Added Jun 2012 13k views 5.0 stars (7 votes) •Cock Growth•Huge Cock•Transformation•Aliens

The trainer by Also Known As Needing a new trainer, Thomas finds onewho can push him to the next level, and then some. 7 parts 22k words Added Jan 2014 26k views 5.0 stars (14 votes) •Always Hard•Cock Growth•Huge Cock•Muscle Growth•Muscle/Strength•Size Increase •M/M

Unexpected consequences by Alex 2 parts 5,254 words Added Oct 2005 17k views 5.0 stars (3 votes) •Cock Growth•Huge Cock

Secret Santa by BRK Joe’s crew at his new firehouse are destined to become very important to him, but the extent to which he’s more and more heart-thuddingly attracted to his handsome, well-muscled workmates worries him more than a little. 3 parts 15k words Added Dec 2016 17k views 5.0 stars (15 votes) •Cock Growth•Huge Cock•Multi-abs•Multiarm•Multileg•Multilimb•Three Legs•Replication•Muscle Growth•Muscle/Strength•Always Shirtless•Incest•Brothers•Selfcest•Christmas•Complete •M/M•M/M/M/...