The protagonist, who was once said to be the strongest tactician in the human army, is killed by a plot by an aristocrat. Moreover, the nobleman is said to be living a rich life without being punished. “This world is wrong!” The protagonist, who was reincarnated as the demon king's lieutenant, punishes the high-ranking nobles who live in solitude, and in order to create a new world, he leads a small army of soldiers and defeats the high-ranking nobles, heroes, and stupid bosses.