Fukubu Chiya's daily life was destroyed when the roof of the library exploded. A monster called Rekka, who had been sealed away in an old book in the library, was released, blowing the roof off. Monsters are a dark existence that invade human society. They attack, eat, rape, and kill people during the night... they are nothing less than humans' natural enemies. To fight the monsters, Chiya borrows the power of the old book and challenges them to a fight. This is the story of a human who continues to fight despite being subjected to abuse and humiliation.