About Maou (demon lord); his daughter, Hana; and the heroes. They and others demons transferred to human world after their own world destroyed. It is the story 10 years since they came to demon world. The maou now is just a doting father, Hana become a lone high school girl, and the heroes, they are still wanting to beat the demons

(Source: MU)

One day, Hirazono Satsuki, while walking home from work, finds a girl in a garbage dump. He ends up taking her home and she introduces herself as Riene, an exorcist. She is on a quest to find somebody who took care of her before, a girl named Satsuki. Could he be the same Satsuki?
(Source: Shoujo Crusade)