Ty's heart was racing as this new reality started to affect his body. He'd fantasized about this for almost as long as he'd been aware of his sexuality- finally he'd be able to experience becoming a girl! He looked around at the reflective walls of the chamber, practically shivering in anticipation.
Just to tantalize him, the first changes were quite small. His face subtly reshaped, his figure slimmed and his shoulders narrowed, and shivers ran through him as his body adjusted. He watched as his hands and feet shrank and his arms and legs turned more lithe and shapely. An odd feeling in his throat accompanied his voice rising in pitch, and he felt his body hair recede inwards practically everywhere except his head, where it lengthened rapidly.
One last change affected his figure, his hips widening and his butt enlarging, before the femininity building inside him started to emerge in his genitalia. A warmth filled his chest as his nipples suddenly grew larger, puffier and softer. He felt a softness spread through the flesh on his chest, and spread all over his smooth skin. Breathing heavily, he watched his chest grow, until he had soft warm C-cup breasts.
As the changes finally neared completion, they finally seized his manhood. Ty felt an odd sense of satisfaction as his cock started to recede into him, like it had fulfilled its purpose and he... SHE... needed to adapt. Now he had bred, she needed to get bred. As if capitulating to that need, he felt his balls move up inside her, and a vaginal slit soon formed between her legs, while his penis shrank to a tiny size and grew more and more sensitive as it slowly formed her clitoris.
Once her changes finished, Ty- or Tyra, as she decided would be her name as a girl- looked at herself in the reflective chamber walls contentedly. She lay down on the floor and spread her legs, waiting for the chamber to deposit a boy for her on the sliding floor.
He emerged a few moments later, and Tyra looked up at him and was instantly taken by him. He had a handsome face, toned body- not too muscular but clearly fit and attractive- and an impressive 7 inch shaft, longer than her own had been. He got atop Tyra and she kissed him eagerly, feeling his warm throbbing length between her legs. It slid down her stomach and found her recently formed moist lips.
As she took his shaft inside her, Tyra gasped in surprised pleasure. This felt so dramatically different to manhood, in the best possible way. Soon the boy couldn't help but give into his body's sexual instincts- whether present since puberty and soon to be emasculated, or newly imbued in a former girl, Tyra wasn't sure, but both thoughts were tantalizing to her- and started to pound her faster and faster, rubbing her G-spot with his thrusts.
Tyra's body responded with just as much arousal as his, her nipples and clit feeling intensely hard (the former helped by the boy pinching at them and grabbing at her chest) and her slit clenching tightly around his shaft. Pretty soon, both of them came hard, and Tyra clung tightly to the boy and moaned as she peaked, her pussy instinctively gripping at his cock to keep him from cumming anywhere but inside her.
He groaned and panted eagerly as he shot his warm cum deep inside her, practically certain to fertilize her. She clung to his body as he peaked, until at last his cum was spent, and the sliding floor pulled her away, leading Tyra to the gestation wing...