Shuten Momoko wa Taosenai

The strongest demon meets a monster hunt in this secret-school romantic comedy. Warned by a prophecy that a single demon will bring the Minamoto family to ruin within a few years, Yoriaki Minamoto descends into the Demon Realm to slay the "Demon of the Crimson Sky." In a realm where strength is the only law and the powerful decide how the world works, he conceals his true might and identity as he searches for the strongest demon, only to find something he never expected.