Maou Gakuen no Hangyakusha: Jinrui Hatsu no Maou Kouhou, Kenzoku Shoujo to Ouza wo Mezashite Nariagaru

A normal high school student, Yuuto Morioka was chosen to be a candidate for the next devil king. He transferred to the academy for the devils, Ginsei Academy where he was held in disdain by other students. "I swear I'll make you the devil king. That's why...make me your retainer." Yuuto's encounter with a beautiful devil, Lizel Himekami changed his life and his world. He could learn any kind of magic instantly and absorb magic power infinitely by getting skin contact with his girl retainers. That was a special power that the devil race didn't have and was only permitted for the human Yuuto. The human who became a devil king candidate challenged the strongest devils in order to become the devil king of justice! Exhilarating and fascinating. The fantasy story of climbing up in magic academy is beginning! (Source: Kadokawa, translated)