Mamiya Keiichi (間宮 圭一 Mamiya Keiichi?) second year student in the Ishigami school Sumo club. He took over as captain after the loss to Inter-High Preliminaries
AppearanceEditMamiya is a tall white skinned male with a large physique. He has black eyes and is bald. Both of his thumbs are wrapped in white bandages which expose the rest of his hand, and extend down to his wrist. His mawashi belt is beige in color with the exception of a single green stripe on the left side closest to the front.
- Mamiya Keiichi vs Mitsuhashi Kei
- His blood type is A.
- He uses glasses outside the ring, but when he fights, he uses soft contact lenses.
- He likes idols.
- His family owns a flower shop, as whown when Mitsuhashi Kei bought carnation for Mother's Day in Otake 7. He visited before facing each other in Inter-High Preliminaries.