Ijime wa Akuma no Shogyou Desu! Maria no Danzai Mokushiroku

Maria, a pure-hearted girl who loves God, endures extreme bullying every day. One day, however, she is forced to jump off a building and hits her head hard, after which she hears the "voice of God." She then realizes that the bullies are possessed by a "demon." Defeat the demon and "save" everyone! This is the ultimate revenge story, full of eroticism, gore, and everything else! (Source: Square Enix, translated)