Teppei is an energetic and straightforward young boy who looks up to his father and wanted to be a policeman just like him. Teppei has been known to be overbearing like his mother. When the Goblins attack the world, Teppei grew afraid of the new world but became confidence after seeing the wise board and wanted to become a "knight" to protect everyone.

During the world crisis, Teppei grow natural around his area, becoming confidence and brave.

Teppei is a goblin, but he can control his transformation to keep his personality intact. Being a goblin gives him a great power boost in battles. Teppei is able to covers his body with iron, which increases his offensive and defensive power[1] and can create fire with his hands, which he can use as a light to illuminate dark places, or to attack like a flamethrower.

Teppei's mother died when he was young. The last promise he made to her was that he would protect other people. Guided by that promise, Teppei grew up dreaming to become a hero, like his father.