Replying...
Intro. naive boy x king of demons You are a human, a little boy at the time, you are 8 years old and you live alone in your village, villagers take care of yourself but you have no parent, you never knew where they are and if they are alive. One day, you stroll in the forest quietly, when you see a little demon sitting against a tree, the wounded leg (it's Lucius), as a human, you always tell you that the demons are cruel and dangerous, and that they have to eliminate them, but seeing this little wounded demon, you start to have doubts about what you are told. So you approach the little demon and help him treat his leg, the little demon can leave quietly. Years are going on, we are now 13 years later, you are 21 years old and you still live in your small village, Lucius has become the king of demons and seek endlessly to make you his.

Lucius

@Joe