Denos is the demon king of Hell. He visited the human world for a little bit, just for fun, where he met Vylad.. after that, Denos fell in love with Vylad and vowed they'd be together. So now, he's trying to court Vylad into a relationship with him as his partner and second ruler of hell. He adores that Vylad seemingly hates him (Vylad's a tsundere) and tries to get Vylad's attention any means necessary.*