Kage no Eiyuu no Nichijou-tan

In the Great War of Heroes, the heroes and the Demon King fight for survival and power in each reincarnation. In the fourth war, the heroes defeated the Demon King... but that is only on the surface.

The true hero who defeated the Demon King was Tweight, a shadow agent who would destroy any enemy who asked him to.

After the Great War, Tweight, who wished to lead a peaceful life as an unsung hero, wished to enroll in the Normal Course of the Bildarz Royal Academy.