Herbie watched from inside the locker as Jeff hunched over, clutching his stomach with a groan – the plastic cup forgotten on the dirty tile.
Jeff visibly shuddered. Suddenly, his legs gave out, and the jock almost fell but managed to brace himself against a plastic bench.
“Oh man, what’s wrong with me?” Jeff muttered, limbs shaking.
From his hiding spot, Herbie watched Jeff start to change.
It started small.
First, Jeff’s hands gripping the bench swelled, growing at least two times larger – his grip denting the plastic. His calves tightened, visibly straining his socks, girdle, and pants. In fact, his whole body simultaneously swelled and stiffened against his uniform.
The college boy seemed unaware of these changes at first. Too busy trying to stand without bracing against the bench. Then the changes came faster… harder. It hit the athlete all at once.
“…Hnnghnngg~” Jeff suddenly moaned, eyes wide, blushing - embarrassed. “Wha-,” He started before tensing and gasping as another shudder racked his body. His flesh expanding under his clothing.
Jeff’s uniform was taut, unable to keep up with the suddenly inexplicable growth. The stitching tore at the seams. Finally, it gave. The shoulder pads ripped through the jersey, shredding the material before the laces holding them together splintered under the strain. The pads broke apart and crashed onto the tile.
“OooooooOaaaaH~” Jeff cried with shock and a hint of lust.
His arms swelled, biceps twice the size they were before. His forearms thicker than a football.
His chest broadened, pecs growing firmer, tighter. His form-fitting undershirt straining but holding together at first, muscles firmly visibly through the white elastic. However, Jeff grew again. Taller, thicker. The shirt rode up his chest, exposing well-defined abs and a prominent V-line.
Then, with a loud RIIIIPPP, the shirt disintegrated as flesh and muscle surged – leaving Jeff’s chest bare and glistening with sweat.
Next, his cleats popped with a loud “THWACK!” The leather front fractured under the force of Jeff’s feet growing too large for them – his socks barely holding together. The stench was so pungent that Herbie could smell it from the locker – making him somewhat woozy.
“Hah!” Jeff yelled as he managed to stand, tearing his pants and girdle to shreds as his thighs expanded with muscle and mass. He was left with only a traditional jockstrap to cover his modesty, and even that was losing its own battle.
A thick fat cock and two baseball-sized balls strained the jockstrap to its limit. Even flaccid, it was one monster of a hog – the outline visible from where it pushed against the elastic.
From his hiding spot, Herbie noticed how a musty smell started to fill the locker room. Deep. Masculine. Already woozy, he felt lightheaded but shook it off.
“Hrrrf, hrrrf!” Jeff wheezed; his transformation nearly complete.
He stood, an adonis among men. Cut muscle, thick and broad. Powerful. Strong.
Herbie watched the final changes begin. Jeff’s face was flush; his baby-blue eyes dim – a bright pink bleeding across both iris.
Slowly… hesitantly, his hands started to explore his body – a cocky grin on his face as he felt sharp cut muscle.
“OOOOOOOooooooh~” Jeff loudly moaned when he accidentally touched one of his pert nipples.
His cock suddenly stood erect, shaft and head pushing through the jockstrap, resting against his pelvis – precum glistening where cock met skin.
He continued to massage his nipple, tweaking and squeezing it. With each motion, his moans grew louder – his cock larger and thicker. Soon the elastic band of the jockstrap snapped. Jeff’s other hand wasted no time and wrapped around his thick cock, jerking it with shameless abandon.
“OH GOD~ IT FEELS SO FUCKING GOOD~” Jeff screamed, voice thick with carnal lust.
He grunted as he started thrusting into his own hand, hand slick with pre – his own lubricant.
“Hnngh~! H-Ahhh~! Mmhn~!” The sound of fapping filled the locker room.
Eventually, it was too much for the college athlete. Jeff’s knees buckled, cock swollen against his grip and with one final thrust, “AHhhhh! Fuck! I’m CUMMING~,” He shot big, thick spurts of sperm everywhere; against his legs, the floor, … everywhere.
Each squirt of cum made Jeff moan before he finally collapsed against the lockers – spent. His fat cock twitched against his leg and continued leaking cum, even as Jeff went limp.
Herbie waited a few moments and then stepped out from his hiding place. “Oh,” he paused at the thick odor of cum in the locker room. It was strong… and…
“Uugh,” He shook off whatever the feeling was and placed a hand against his nose, doing his best to stop the smell from affecting him.
Cautiously he kneeled next to Jeff, waving a hand in front of the downed footballer. Nothing.
Jeff had a vacant expression. Bright pink eyes unseeing. Drowned in his own pleasure.
“Hah!” Herbie joyously exclaimed. “Who’s laughing now!?”
This was perfect, his serum worked! Jeff and his football bros had tormented him constantly. It had only gotten worse when they found out he was still a virgin. The sex-obsessed college athletes never let him forget about how often they got pussy. It was their carnal desires that inspired him. He’d make it so they never forgot about how horny they were; in fact, it would be all they could think of ever again.
Kneeling beside the hunk of a man, Herbie reached out and poked Jeff’s nipple, watching amazed as the jock's penis twitched and cummed all over his leg.
“Heheheeee~,” Jeff giggled. Lost in pleasure.
Herbie stood up. “You were already dumb, but look at you now,” he said, admiring the results of his serum.