Suddenly, as the world began to take effect, Ty's clothes vanished. He looked down at his body and noticed his penis was becoming hard, as the amplified sexuality of this changed world began to take hold of him. Unable to contain his excitement, he grabbed his cock and began masturbating like an animal in heat, rubbing it eagerly while a million sexual fantasies played out in his head.
He was so horny by this point he didn't even notice his fantasies becoming more androgynous; he was imagining not only fucking beautiful women, but getting fucked by handsome men. The warmth from his cock was spreading through his whole body, and he felt his skin becoming softer and smoother. He suddenly noticed his nipples were enlarging, pinched one... and had to bite his lip. It felt so good, so sensitive, and he found himself rubbing it and the other with his fingers, and cupping the enlarging flesh forming around them.
As he massaged his enlarging breasts, his body was changing between his legs too. His balls pulled up inside him, the loose sac of his scrotum narrowing and forming into soft vaginal lips, with her body opening out as her vaginal tract, womb and ovaries formed inside her, while her penis rapidly receded into a little nub, far more pleasurable than its male form. One of her hands moved between her legs to touch it, and between the pleasure from her breasts and her clit she came, her body clenching with muscles that minutes ago had served exactly the opposite of their current purpose, moaning excitedly with newfound pleasure.
After recovering from her orgasm, Ty looked at herself worriedly. Why did she turn into a girl? Was she stuck like this? Before she could really worry, though, she felt her body seal itself up, testicles return to a reforming scrotum, and her clit rapidly enlarge into a cock. She realized she was able to change her body to match the gender she felt at any given time, and that everyone she was to have sex with would understand and not question this.
Giggling, she let her penis shrink back into its clitoral hood and her scrotum re-open into vaginal lips, and began to consider what she wanted to do.