A dark fantasy where Heroes-criminals sentenced to heroism service in a penal military unit-must wage war against a demon king's army.

After a life-changing incident, timid college student Koichi Haimawari accepts an offer from revered vigilante Knuckleduster to train as his protégé.

Yuhi and Yasumi, who are both voice actresses that attend the same high school. They host a radio program together. They are diametrically opposed in appearance and personality, and they get into fights when they are not on air.