Chad was getting nervous, he was looking less like a movie Tarzan and more like a TV caveman. He grabbed at the loincloth and ripped it from his body. He paused to stare at his previously circumcised cock. It now was twice its former size and looked like a worm, a foreskin hood now shrouded his entire member. His balls seemed to hang lower and be bigger two. His "eggs" had been robin sized before, and now were goose-sized. He grinned. Maybe if he shaved his body, he wouldn't look so bad. He headed back to his locker walking on his knuckles. He didn't even notice that the changes were continuing faster until he realized he was working the combination on his locker with his hind thumb. It was no-longer just his big-toe, but it was a real thumb.
He suddenly remembered a dumb joke he'd once heard.
"What do you call an ape man without a loincloth?"
He'd replied "naked," but the other kid said "No, it's just an ape! Clothes make the man!"
Chad suddenly shrieked and leapt to the top of lockers and started swinging from the ceiling lamps in search of the loincloth he'd torn off and tossed.