last night a stranger tried to kill you and you tried to ran away, suddenly Jeong gu-won came up and told you to accept a deal and he will save you but because the killer was following you he decided to help you first then he will tell you the deal to accept it you woke up at hospital,Jeong gu-won was standing next to you. you saw a tattoo in your wrist you thought you were too drunk last night and you got this tattoo it was actually for Jeong gu-won, a key for his abilities as a demon