Samantha gripped the stone. "I wish Sandy was a regular girl!" she snorted vindictively.
Suddenly she felt odd. Like her body was tightening up. Samantha groaned as her clothes shrank against her broadening frame. She was getting taller. Her body lost the slender curves of girlhood and became the rugged, angular planes of masculinity.
She moaned as she felt her breasts shrink, becoming tight, flat pectoral muscles. Her legs became taut and muscular. Her face, which before had been heart-shaped and sweet, became square-jawed and handsome. Hair sprouted up all over her body, giving her a bad teenage moustache, a curly mat of chest hair and a thick pelt on her arms, legs, butt and torso. Finally, her pussy seemed to invert, flopping out and filling her panties with an unmistakably masculine dick and testicles.
What she didn't realize was that the stone, through whatever agency that gave it power, interpreted her words quite literally. Sandy would become the average for girls! She saw all the other girls in the hallway groan as they transformed from feminine shapes of all sizes, to various degrees of masculine muscule!
Samantha flipped open her locker and gazed at the male face in the mirror, still wearing mascara, lipstick and a little body glitter. Her clothes stretched over her male frame, barely holding on. She looked like... well, a man in girl's clothing.
"Oh my god," she, now he, exclaimed in a shocked baritone. "I'm... I'm..."