"Ok, this should be good then. I've tweaked my initial plans to make this more... Comfortable for you." Kyle said after a moment of thought. He hadn't been prepared for her to be so willing to change, and hopes that he isn't making a mistake by leaving himself open to retaliation.
He took a deep breath and began. "For your transformation, you will become a giant. You will be an androgynous man, twenty feet tall, and with a proportionally large dick and balls. So that your new size causes minimal issues, your new body will be extremely flexible, able to squeeze through a normal sized doorway with little trouble. Since you'll be too big to feed off of normal foods, you can eat people whole for sustenance. Any damage you do will be repaired by the next day, and anybody that you eat will 'respawn' next to their bed two to five days later. Everyone else will treat your changes as new but not strange, and you'll occasionally find clothes and other objects sized for you around town, although they will all be distinctly feminine."
Jennifer felt a tingling in her body. "Whoa I feel it starting! Haha, it feels weird!" Her clothes were already becoming tight, seams beginning to snap.
"Come to school if you want to say thanks Jen, I'll see you there." Kyle said before hanging up.
Jen was already forced to crouch as she passed ten feet tall, and beginning to notice that her breasts were shrinking back into a flat chest.
With a final snap, her skirt's elastic gave way to her widening waistline, leaving the twelve foot tall girl nude in her bedroom. Although she wouldn't be a girl for much longer, as a tingling in her pussy grows stronger.
Twisting herself into position to watch, Jennifer slipped a massive finger into her pussy for the last time, feeling it shrink around her digits. Her clit had grown larger, lengthening and shifting from pink to match her skin tone.
Her other hand began stroking this new clit-dick, pleasure flowing through her body as her finger is finally pushed free by her new balls finally inverting his pussy.
Now both hands were free to masturbate his cock as it reaches a fully erect length of three and a half feet. He began to moan as his gender solidified to male. Curling himself further he slipped the head into his mouth and began sucking. His newfound flexibility let him get a foot of cock in his mouth without struggling, and he could probably deepthroat it to the base without much trouble.
"Mmmphh!" His eyes went wide as his first male orgasm hit, sending his seed straight into his stomach. His legs kicked out involuntarily, blasting a hole through the wall.
"Fuck that was good..." The man said, pulling himself outside through the hole. "I should probably go to school though." He looked around, noticing that he was as tall as his two story house, as well as the wreckage of his bedroom. Something pink in the backyard caught his attention, and he went to investigate.
It was a massive backpack, similar to the one that he had used as a young girl. Inside was a notebook and pen, also sized for your use.
"This is so cool! I definitely need to say thanks to Kyle." He says as his stomach rumbles, "I should get breakfast first though..."