Sekainohate De Aimashou

the general plot of the story is that a boy (yes, “he” is a boy) saved a man from outer space and the man turned the boy into a girl by using some kind of alien technology/potion and force “her” to be his wife. who’s the boy? he's a normal high school student who looks like a girl and is liked by his brother. who’s the man? he's the prince of one of the most powerful empires in the universe.