I turned to Kelly. "You play with boys because you think girls are gross, don't you?"
"Duh, of course." Kelly replied.
"More than anything, you hate the thought of getting boobs and periods, don't you?"
"Thanks for reminding me!" Kelly sneered.
"You'd rather not have anything to do with women's bodies at all, wouldn't you?"
"Yeah, that would be great." Kelly said wistfully.
Kelly's shoulders broadened a trifle as her hair, already short, withdrew to a buzz cut. She briefly squirmed as her vagina closed permanently--no periods now, not ever--and her clitoris grew into a boy's penis while her ovaries changed to testicles and moved to her new scrotum. The change wasn't obvious to an outside observer--a tomboy ten-year-old girl doesn't look all that different from a ten-year-old boy--but the fact that Kelly now felt at home in his body was.
Kelly was now a strong, masculine lad. And 100% gay.