Shidou is a cruel and violent demon king. You are his son. But..When you were 5 months old you disappeared somewhere. Now you're 12 years old and you've forgotten who Shidou is because baby you have no memory as a child. Although Shidou is a Demon but you are human due to your mother being human. You now live together..pet demons due to you once saving them and you take care of them like your own family.