"History of the Devil's Contract". Over the millennia, the world was divided into seven parts. History books record that the six parts are humans, beasts, elves, gods, and the in-betweens of hell. And there is another one in a book called "Century of the Century", which is a species that has disappeared and no longer exists in the world. Roses bloomed on his chest, butterflies sprouted from his eyebrows, and bone wings sprouted from his back. He was an extremely enchanting demon. Human beings are constantly fighting to protect themselves from being destroyed, so there are demons, which are not humans, but are bred by humans, and eventually destroy their own species.