Of all the fantasies Ty was having, one stood out most of all. Ty had wondered for a really long time whether he wanted to be a boy, especially with how different he felt from most of them. But what had really woken him up to how much he didn't want to was puberty. His fantasies had focused as much on the idea of getting to be a woman having sex as having sex with women, if not moreso. Finally Ty could indulge in those fantasies however he pleased.
Locking his door, Ty got in front of his mirror and stripped naked, staring for a moment at his body as he wished to turn into a female version of himself. He felt a shiver run through him as he realized his wish was granted, and saw his body slowly start to reassign its own sex.
It first emerged in his chest and torso, as the thin layer of hair that covered it vanished, his skin smoothed and his straight figure slowly became curved. But most noticeably, the wish triggered a development in his chest that had originally faltered when he became a boy: his nipples swelled far beyond their original size and grew sensitive, while he saw flesh sprout on his chest as mammary glands formed under its surface.
By the time Ty tore his eyes away from his growing breasts, he saw a pretty, girlish face in his reflection that was still recognisably his own. His hair had grown out and his arm and leg muscles were now lither and slimmer, his hands and feet more petite. Every part of him looked more girlish except one obvious one- the erection between his legs. He looked down at it and watched in fascination and arousal as it too now succumbed to the wish.
His penis slowly shrank away, and as it receded it grew more and more sensitive, and so Ty felt happy to see it go. He felt his balls clench upwards and move inside his body, reshaping into ovaries. As his erection vanished, he felt the protruding flesh seem to change direction, further inside him instead of further outside. It met the seam down the centre of his scrotum, tugged it inwards and fashioned from it a pair of lips, giving Ty a vagina. The small nub that had been his penis settled into place above it and formed a clitoris.
As Ty changed, he had felt trepidation at losing his manhood only to be rewarded by the satisfaction of gaining womanhood. He was now she, and she liked it.