Ty and Dustin both snickered as they saw a small boy walk in. Ty read his mind to learn what he could about him.
Jack was 13, but looked one or two years younger. He was a bit on the small side, but still fairly average. He was coming from a practice for soccer, and as such still had his shorts and shirt from practice on. He was just using the restroom. Oh this is gonna be good, Ty thought.
Jack walked up to a urinal and pulled down his shorts. He expected to start peeing, but instead he felt a tingle sensation and then a wave of pleasure. Jack stood groaning as his cock grew longer, stretching from its previous 5 inch size to 7 inches, then 9, 11, 13, and finally 15 massive inches of rock hard cock stood straight out in front of him. Jack's balls had also doubled in size to become the size of baseballs.
The surge of testosterone from his balls just after their growth caused a series of changes in Jack. He shot up several inches, to six feet tall. His shoes busted as his feet grew right out of them, his muscles all bulged as he gained about 10 pounds of muscle, and his voice dropped an octave mid-groan.
Finally, the wave finished. Jack stood, much heavier than he was just previously. His clothes were holding on for dear life, his shirt was practically skin-tight. Jack managed to stuff his enormous cock and balls into his shorts, causing an obscene bulge in the process, and lumbered out of the room.