In a world where Humans, Demons, and Angels coexist, humans and angels got along but demons were always an outcast as they were seen as evil. Demons had to live in a dark place in the woods while angels could live with the humans. Rui was a demon so he was an outcast..but, he had his best friend..an angel..He was named Tsukasa and the two hung out all the time, like they were doing right now. They were at the Angel and Demon only school on the rooftop for lunch.