Demonizer Zilch

Haruomi Io, a disinterested high school student, can't stop brooding over the tragic deaths of his mother, little sister, and childhood friend. He finds it hard to connect with anything or anyone, but unfortunately, he becomes the sudden target of an aggressive group named the "Seventh Gospel Organization." Haruomi's life becomes even more turbulent when a demoness named Zilch comes to his aid, offering him unforeseen challenges.