--- Originally posted on 2021-04-15 by newyoutf ---
Alex opened the door of his apartment and threw his keys onto the counter, his eyes darting around. He’d been expecting a delivery today, the delivery notification came in just minutes ago.
“God damn Bryce, couldn’t even accept the delivery, the one favor I’ve asked,” Alex thought to himself.
Bryce was Alex’s roommate. A large, handsome jock of a man; quite the opposite of Alex. If Bryce wasn’t home he’d be at the beach, the gym, or out hitting on everything that had a pulse. Alex had always had a love/hate relationship with the jock, but he was also jealous that he wasn’t and couldn’t ever be muscular and manly in the same way that Bryce was.
“Hey, Bryce, you here? I had a delivery?” Alex asked loudly.
A few days ago Alex had seen an oddly specific ad in his Instagram feed for a special kind of spray-on supplement that claimed to be able to “bring out the jock in you!”. The twenty-four-year-old had been trying desperately to pack some weight onto his thin body, and in that desperation, anything that claimed it might help was an option.
Alex walked toward Bryce’s room, the door half shut but the light still on.
“Oh yeah man, got it here!”, Bryce’s unmistakable, deep voice echoed out from behind the door.
He opened the door to see the small box open on the floor, the shipping label torn through the middle with the words “From: New You Inc.” still partially legible.
The six-foot-two Bryce was standing at his desk, shirtless, with his strong, hairy chest on full display. Alex spied a small spray canister with the label “Jock Formula” written across it in Bryce’s meaty hand.
“No!“ Before Alex could stop him the dimwitted stud pressed down on the cap and sprayed it under his arm.
“Huh… it’s already empty?” the jock said, confused because he hadn’t bothered to read any of the included writing.
“Yeah, it’s a single dose, Bryce! That shit was expensive,” Alex bemoaned, barely containing his anger.
“Oh shit, sorry man,” Bryce turned to face Alex, a regretful grimace crossing his handsome face.
“What’s the deal anyway, it smells like… sweat? Aren’t these sorts of things meant to smell good?” Bryce said, sniffing his hairy underarm.
“That’s probably just you. It’s not a fragrance anyway, it’s was meant to be some kind of supplement, to help me you know, bulk up a bit,” Alex replied bashfully.
He snatched the empty canister from Bryce’s hand and examined the bottle, reading the fine print on the side: “Single-dose only. Warning: Strictly for use only by men who do not match the description of a jock. Effects are unknown outside of this group.”
“Weird warning... Whatever, it was probably just a scam like all the rest anyway,” Alex thought in defeat as he turned to leave Bryce’s sweaty room only to be startled by a heaving groan from behind him.
“Augh!”
The loud, lurching moan made Alex jump. He turned to see Bryce bracing against the desk with his mouth hanging open and breathing heavily.
“Ugh, fuck!”, Bryce lightly thrust his hips forward and slumped into the desk chair sitting next to him.
“Bryce? Are you okay?” Alex spoke slowly with genuine concern.
The jock now had an enormous, raging boner visible through his loose gym shorts. Alex blushed staring at the outline of his hunky roommate's long, thick cock.
“I… I think I’m having a reaction or something man...,” Bryce moaned, having difficulty moving off the chair. He tried repeatedly to stand only to moan and fall back down.
Alex thought back to the odd warning label on the bottle and began to panic. What would happen if a jock tried to use the spray? Bryce’s rolled his eyes back as he thrust slowly and deeply upward. A large, damp patch appeared on the front of the shorts, followed by large loads of cum seeping through the fabric. Alex watched in astonishment as the stained shorts began to disintegrate, revealing the throbbing eight-inch cock that was contained within. Bryce heaved and moaned as ropes of cum shot up his thick abs.
Something about Bryce’s body looked unusual at this stage. Alex could have sworn the tall man looked a bit shorter. Indeed, Bryce was shrinking, and at a rapidly accelerating pace. His chest appeared to flatten and his muscular limbs deflated and retracted. His entire body was taking on a fabric-like texture as it rapidly receded inwards. Soon, all that was left of Alex’s roommate was a jockstrap sitting in the chair.
Alex stumbled backward in shock and sat on the side of Bryce’s bed. His mind was swirling with panic as he clasped his hands over his face, certain his situation was a bad dream and that he’d wake up any second. A light thud followed by brushing across his ankle caused him to lower his hands and see that the jockstrap had moved itself to the floor and attempted to push itself under his feet.
Alex screamed and recoiled his legs from the floor, jumping upright and unwittingly giving the jockstrap the perfect opportunity as it flew up his legs.
“Fuck! Get off!” Alex yelped as he hopped across the floor, slamming into the desk and drawers trying to pull the material away from his shorts. His horror only deepened when his shorts sizzled and frayed in contact with the jockstrap, melting into the air within seconds. His briefs met the same fate only moments later. There was no contest to be had. The jockstrap easily forced its way up his now bare legs and wrapped itself around his ass and cock.
“What the fuck?! Get off! G- get... augh!” Alex hunched over, stabilizing himself on Bryce’s desk. The sensation of the jockstrap hugging his soft cock was mind-blowing. Between gasps of pleasure, Alex heard a quiet cracking, whimpering in response as his legs began to creak, stretching longer. He thrashed backward from his hunched position allowing his back to soar taller. Alex’s arms felt heavier as they too stretched longer. Groans escaped his lips as the lengthening stopped. The formerly five-foot-nine man was now a lanky six-foot-two. However, he wouldn’t be lanky for long.
Alex’s thighs ached and pulsed. He placed his hands on them, groaning as the muscles swelled and expanded. He pushed harder into the throbbing muscles as if pushing back might stop what was happening. But the thighs just continued to bulge with muscle.
The straps around Alex’s rear tightened harder and harder as his ass swelled into them, round and firm. He grunted, shooting a massive load into the jockstrap while his cheeks expanded. Brown hair began to swirl out of the perfect globes and across his massive legs. It spread across his shins while his calves bubbled and bulged with strength.
Something about Alex’s new legs looked vaguely familiar to him, but his train of thought was interrupted by the upward spread of the changes.
“Please... no,” the groans bubbled from Alex’s throat as his stomach began to tighten. Looking downward he could see the soft outline of abs appear. The bulges of muscle only deepened as the abs thickened further. He delicately and fearfully brushed his hands against his new abs. Those legs, those abs... Alex recognized them now. They were unmistakably Bryce’s. His mind was gripped by fear, “No... no... I can’t be...”
He lurched and gasped feeling his nipples become erect, begging to be touched as muscle began to form below them. Alex blew another load feeling the thick, meaty pecs surge forth from his chest, coated in a dusting of dark, manly hair. Whatever doubt he had was washed away, this was his roommate’s chest. Alex couldn’t help but think ahead, that he’d gain Bryce’s muscular arms, his looks, his massive cock. Fear quickly gave way to desire. He couldn’t resist, he was turning into his hot roommate and the thought turned him on immensely.
“Oh fuck yeah,” a smirk crossed his face as the pressure rose in his shoulders, groaning as they pushed outwards, growing and broadening. He gripped one of the biceps with his hand tightly feeling his skinny arms begin to inflate. His biceps and triceps gradually swelled and packed on strong muscle, his grip being forced more and more open, unable to come close to holding the beautifully thick arms. Alex’s cock pulsed hard at the realization these dominant, muscular arms were truly his. His thin forearms writhed and twitched as muscle blossomed and grew within them. Veins snaked across them, running down his hands, and followed by a trail of new hairs. Alex held his trembling digits in front of his face, watching and feeling his palms creak and expand. The fingers twitched as they soared outward into the air, growing unbelievably long and proportionately meaty. Alex moaned in delight at the feeling of the weight and size of his new digits.
The same erotic stretching sensation that plagued Alex’s hands next infected his feet. Knowing that Bryce wore a size twelve, Alex knew what he was in for as the toes on his size eight feet began to stretch longer. His toes raged against his no-show socks, stretching the cotton beyond belief. Beneath the thin, strained material he could them stretching longer and thicker before they tore through. The hairy digits twitched and throbbed as his soles spread longer and wider across the floor. Alex gawked at the big feet, recognizing them as Bryce’s, but now his own.
Alex growled in anticipation as the changes rippled up his neck, causing it to widen and thicken. His sensual grunts lowered in pitch as his vocal cords morphed. His nostrils flared outward and inhaled deeply as the small button nose grew longer and thicker. A sharper, broader, more attractive jawline emerged from his face while his cheekbones shifted. His cock drooled with the knowledge that he was transforming into his handsome, jock roommate. The short hair on his head thickened and grew out, gaining waves and curls while darkening a shade. His teeth glimmered as his smile becoming a cocky smirk no one could resist. Reaching to his face, he could feel the short stubbly beard that Bryce usually had forcing its way out.
Alex turned to the mirrored wardrobe at his right, drenched in sweat, and immediately released a massive wad of cum at the sight of the manly face, Bryce’s face, looking back at him.
Alex felt his balls surge and rumble as they inflated. Emptied of cum from repeated orgasms prior, he felt them weighed down heavier, filling with new, hot, jock cum. He smiled with a dumb, devilish grin as his cock began to quiver and throb, signaling what was next to come.
An inhuman roar spilled from Alex’s mouth as his cock began to swell in size. The head bulged against the jockstrap, bloating outward and spewing more cum into the soaked jockstrap. The lengthening cock shoved against the material, pushing it further and further away from his waist and offering a view of the thickening, veiny shaft within.
Alex muttered under his breath, enthralled by the sensation of his cock morphing into a carbon copy of his roommate’s. He rubbed his hands across his beefy pecs and abs, taking in his new form and embracing the big, manly jock he now was.
His cock bounced upward as it slipped out the top of the jockstrap, having grown too large. The front of the jockstrap snapped back elastically against the top of Alex’s hairy legs. He gazed downward, panting at the massive, pulsating cock. Cum oozed out of the mushroom head, running down his eight-inch shaft. It quivered, longing to be stroked, and Alex was all too happy to oblige. He gripped the monster in his hand and throttled it.
The jock couldn’t last long, given he'd been teetering on the brink since the very beginning. Alex bellowed as the most intense orgasm of his life rocked his entire body. His large balls tensed as cum repeatedly rocketed out of the hard python, spraying up his hard, muscular chest and across the room; his shy, nerdy personality traits being pumped away with it.
Blinded from the pleasure, his mind blurred, the gaps that had formed being filled with new traits: sports, the gym, and sex were all that mattered to him now. Once the post-orgasmic glow passed the new and improved Alex made a stupid grin, impressed with the mess he’d made.
He stuffed his large, soft cock back into the jockstrap, smearing it with sweat and cum. He shuddered, feeling something strange across his body as if a moan were echoing out from the jockstrap.
He looked down at the piece of fabric, “Hey Bryce, hope you’re liking it down there, bro,” Alex snickered as he adjusted his package.