The door creaked open as Ty walked into the Gent's Toilets. He heard some animalistic grunts coming from one of the stalls to his left.
"That must be Matt", he thought.
At 6'8 and 220 lbs, Matt was one of the school's biggest residents. He grabbed his huge pecs with his left hand, twisting one of his big nipples as he stroked his fat cock. His biceps bulged with raw power as he masturbated feverently in the cramped stall.
"Hmm ... Matt is big .... but not big enough yet. Let's see how the walls fare against a growing football linebacker.
As soon as Ty made his wish he heard a change in the grunts behind the toilet stall. The young jock's tone became lower as his body began to pack on mass. Inside the stall, Matt's hand continued to grope his massive pectorals, unaware as they began to expand into thick slabs of muscle. Striations formed as they expanded like a shelf overhanging the rest of his gargantuan body.
His abdominals began to rise like bread in an oven as his hand strayed from his fattening nipples to tracing the swelling abs. His shoulders broadened bigger and bigger, filling up until they pressed against the walls of the stall. His glutes encompassed the lid of the toilet that he sat on, and sounds of creaking emerged as the muscled football player expanded into a muscular behemoth.
All the while, Matt was focussing on getting himself off.
He continued to grunt louder, filling the now tiny stall with his enormous jock body. His thighs grew so much that his knees pushed against the doorway to the stall, calves swelling to the size of the biggest bodybuilders'. His size 15 feet peeked under the stall door, where Ty stood impressed by his handiwork.