He thought to himself about how bad relations between the sexes were. And all because of differences in anatomy.
Of course, as he thought more about it he realized it wasn't just anatomy, it was the entire body. But what if that changed.
He wrote down a bit in the book and crossed a lot out. Breasts; unneeded, those need to go, deep voices in men, wide hips in women, differences in face structure, all of it could be discarded. Actually, if you thought about it all if it was counterintuitive to mating. The only thing anyone needed was genitals. He left in a clause to make sure he remembered everything, as would a few random others, but the vast majority would think the world was always like this.
Pretty soon the only difference between men and women would be between their legs. Once the transformation started he looked at himself in the mirror, he was young and attractive, but his face was already bringing to change, his skin became softer, his facial hair faded, his features became less masculine and more and more of his maleness began to fade.
For a moment he was fascinated, his body changing infront of him. But another part of him was horrified, regretful of the change. But soon it was all over.
He looked at his body. He was still attractive, but in a different way. He was more beautiful then he was handsome, his skin delicate like a woman and his features much more feminine. His body was truly and completely androgynous, if he didn't already know he wouldn't be able to tell if he was a man or a woman. There was just this complete lack of male or female traits.
He took off his clothing to check the rest of his body, he was so hairless and skinny now. But when he looked down he saw that his cock remained unchanged. While it no longer had external testicles to frame it, it was very much still his cock. And from looking at himself he could see it was very functional. He was what most would consider a trap, though he reminded himself this was normal now.
He looked at a picture of his girlfriend, yep she was changed too, he cute little breasts were forever gone. He liked her like that though, she was attractive in a new way, a more nuanced and subtle way.
This was going to be an interesting world.