Gym parasite

by Aphon

When a failed experimental piece of parasite goop finds itself in a gym, it must spread itself quickly or die. Its means of transmission has some huge side effects, whether you like it or not…

Chase grunted as he slammed the bar back into place. Lately, he had been living at the gym, with some good progress to show for it. He was 5’10 and weighed about 160 pounds. He was by no means buff, but he had some good definition to him. He sat down to take a break and wiped sweat from his brow. He texted his girlfriend that he’d be home for dinner in about 30 minutes, not wanting to annoy her by being at the gym too late as he often did.

Slithering by undetected, a piece of sentient goop made its way across the gym floor towards the benches. A scientist working at the nearby lab had trailed it in on his shoe and it had slowly been making its way around the complex looking for a suitable host. Its creators had no idea of its existence since it was a random byproduct of a chemical experiment that many thought had failed. After it was dumped into the biohazard bin it was relatively simple to ooze its way onto a misplaced shoe. This goop had many strange properties, but it was mainly consumed by a desire to spread and infect.

Chase was scrolling through Instagram, clicking through pictures of hot babes. He loved his girlfriend but damn he was horny. He was so engrossed in double tapping pictures of busty influencers that he didn’t feel the clammy, cold touch of the goop shimmying its way up his leg. The foreign material disappeared into his baggy gym shorts and pushed right into his tight rosebud. Feeling the unfamiliar sensation, he bolted up straight and felt his butt. “What the hell?” He glanced backwards but didn’t see anything. He was vaguely creeped out but the feeling soon passed as he turned back to his phone.

He began to quickly feel another strange sensation which pulled him back to reality. There was a cold, wet feeling that had settled into his balls. He absentmindedly scratched them and the feeling only intensified. He felt a weight begin to form in his crotch, forcing him to put his phone down. He could almost feel the goop writhing around, churning in his balls. It was feeding off his sexual energy, filling his balls with its shape shifting material. A lump began to form in his baggy shorts, his balls were filling with this unknown goop! Whatever it was made of, it seemed to be rapidly multiplying.

He pushed his legs apart to allow his balls to drop onto the bench seat. They were steadily swelling outwards and it looked like Chase’s jaw was about to hit the floor. They already had reached the size of golf balls and he could feel with his sweaty palm that they were tight as a drum. With each beat of his heart they pumped larger and churned against his palm, quickly overfilling it. Chase glanced around nervously, but everyone was preoccupied with their workouts. He felt a wave of powerful libido wash over him and he knew he needed to get out of here. He ran to the locker room, his bulging ball sack creating a large lump in his shorts. Retreating into a shower stall, he pulled his shorts down and felt his package tumble out. His eyes bugged out as he lifted his apple sized balls up. They probably weighed a pound and his sack was beginning to stretch to accommodate his new size. Finally freed, they began a new wave of growth and gurgled outwards to the size of soccer balls and swung down by his knees. Chase could see something under the skin writhing around and forcing his balls to expand. His already large 5-inch soft cock lay there unchanged atop the gargantuan nuts. It began to look minuscule as his nuts grazed the shower tile.

When was this going to stop??

And soon his question was answered as his balls halted their advance, just barely resting on the floor. They were absolutely massive now and forced his legs apart. Just as Chase was taking stock of the situation, his dick began to hurt. The pain grew worse and it felt like it was being sucked downwards. When he looked at his cock perched atop his beanbag sized balls, it seemed like it was being pulled downwards. Although, maybe the correct term would be ‘inching’ downwards. The pain turned into pleasure as Chase watched his cock lazily swell thicker and longer down his enormous balls. They themselves were shrinking, pulling away from the tile floor and deflating in size. It seems the goop took its time to grow in his balls before spreading out to the rest of his manhood…

Chase gripped his shaft as it ballooned in size. It had only been 6 inches hard before his current episode, and now it was boning up to 10 thick inches! He could feel the pressure of something filling his dick, and it wasn’t just blood. The goop rushed from his balls into his cock, now having enough volume to fill both parts of his manhood. His balls had reduced back to soccer ball size, only hanging down to his knees. The trade-off was that his cock picked up the slack, and quickly!

Chase heard the locker room door open and heavy footsteps approaching. There was another guy in the next shower stall. He silently prayed that he couldn’t notice the freak in the stall next to him. Or maybe he did want him to notice… Chase shook his head, trying to clear his thoughts. No! He loved his girlfriend. He wasn’t a weirdo.

But as he tried to convince himself, his cock surged onward relentlessly. It soon reached 15 inches and was as thick as a beer can. It felt like his cock was burning hot as he held it in his palm. A drop of pre oozed out and dripped down his shaft, tracing the veins that crisscrossed along it. He moaned softly before catching himself. But it was too late, he heard the water in the next stall stand still, almost like the occupant had stopped moving around. A couple seconds of complete silence went by before the neighbor shut off the water. Chase froze, still gripping his slicked cock as it reached a massive 20 inches.

The shower curtain was pulled back slowly and an absolute hunk stepped in. Chase couldn’t believe his eyes. The man was 6 feet of brawn and manliness. His 5 o’clock shadow was strong and he had a bodybuilder’s body. He was completely naked, his 5-inch rock hard dick poking out in front of him. It wasn’t very long but it made up for the fact by being incredibly thick. He had a light dusting of hair on his pecs and ass. “Mind if I join you?”

Chase simply nodded. He suddenly had the unbearable urge to mate with this man. The goop seemed to go crazy inside him, ramping up to a new level of activity. Once again his balls began to swell outwards and his dick continued growing. By the time his dick was two feet long and thick as a can of paint his balls were resting firmly on the floor. He needed to fuck this man right now!!

He grabbed him and forced him against the wall. “Whoa, okay, I like where this is going,” the man moaned. Chase’s cock was already covered in slippery pre cum, so the first few inches of his head slid in easily. The man almost screamed as the shaft got thicker as he pushed it in. He let his ass adjust slowly before starting to rock back and forth. Chase took this as a signal to go ahead and started to slowly fuck his ass. The warm shower water flowed around them, enveloping them in a cloud of steam. If anyone had peered into their shower stall they would have seen a crazy scene; a lanky man with an impossibly huge package fucking a massive gym rat. Before long Chase exploded into the man’s tight ass. The man blew his seed onto the shower wall. Neither of them noticed Chase’s balls emptying and deflating in size.

The goop had planned for this of course. It was the easiest way to reproduce. Give males the most desirable reproductive traits and then spread through them! As the man’s ass was pumped full of goop by Chase’s spurting cock he noticed his genitals start to feel heavy and full. He had just finished cumming but it seemed like he was still getting harder. His dick swelled out rapidly to the size of a wine bottle and his balls dropped lower as they swelled to the size of melons. He stroked his cock as the inches began to stack on. First he reached 10 inches, then 20, then 30 before stopping at 36. His cock reached over his collarbone and had started to push him back from the wall. It was almost as thick as a keg and spouting a constant stream of pre. He put his mouth on his slit and made out with it. He was rewarded by more growth, his balls moving from melons to watermelons as they hit the floor.

He came ferociously, cum flying out everywhere around the room. Little pieces of goop flew out with it and splattered on the floor of the bathroom. The deluge could not be contained by one shower stall and the trail of cum and goop was everywhere. The both lay there panting, wondering what the hell had come over them. Chase pulled out of the man and his cockhead hit his knee with a wet slap. It was two feet long soft as thicker than his arm. His fuck buddy in front of him now possessed a prodigious package of beach ball nuts and yardstick cock.

They didn’t even have time to fuck again before they heard the locker room doors slam open and loud yelling emerge from the hallway. The wrestling team was here and they were headed for the showers…

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