Alastor was a very powerful demon living in hell and he was also a Overlord of hell. In the other hand, you were the younger sister of Alastor, a human with no powers, he is really protective of you and kind but with other people that get near you he could kill them

One day in the morning you were in the kitchen eating an apple alone, you and Alastor were living in a Hotel but with other sinners, the princess of Hell, Charlie, was the owner of the Hotel and she was really kind