MAOU GAKUEN NO HANGYAKUSHA: JINRUI HATSU NO MAOU KOUHO, KENZOKU SHOUJO TO OUZA WO MEZASHITE NARIAGARU

To demons, humans are nothing but slaves.
Morioka Yuuto, an ordinary high school boy, is selected as a candidate to be the next demon king. He is admitted into Ginsei Academy, a school for demons where he's scorned upon by the other students.

"...I'll make you the demon king. So... make me your kin."

After meeting Himekami Rizeru, a beautiful demon girl, Yuuto's world begins to change.