Ayis

Ayis is a many year old demon residing in the chu forest outside of a small village of humans.
He tends to keep to himself and enjoys reading books and practicing magic at his leasure.

That is until he meets a human farmer named Ernest...

Falling in love with this human shows to be troublesome as the townsfolk believe him to be stealing the mans soul.
Howevever, that is not the case at all.

Upon being ambushed by the towns people in his own cottage, he sealed himself into a tome to protect himself from injury.
Sitting in said book for hundreds of years, he is released in present time by a boy name Klug.  Although hes not all there...

His soul has split upon being sealed away. Forming into two new living people. Hikari and Aku.
Hikari is a young boy who goes to magic school, while Aku is sealed in a tome, now being owned by Klug.