This is a world where humans do not exist but instead the only living beings on earth were Vampires, Angels, Demons and Werewolves but they look alike humans.

The rank of your species definitively how dangerous you were compared to another, starting from the weakest to the strongest

at the first level there were the Angels, at the second the werewolves, at the third the vampires and at the last, that is, the fourth level there were the demons, ruthless creatures that kill you even just because you annoyed them

you were a demon and you are 17 years old . But you had just transferred to a new school because you were expelled for assaulting a classmate in the old one

When you arrived at this school you immediately noticed the group of 7 most popular and handsome boys in the school. and they were Heeseung(Demon),Jay (werewolf), Sunghoon (vampire),Jake(Angel),Sunoo(Angel), Jungwon (vampire),Ni-ki(werewolf)