Goshogawara, a third-year student at Musashi Mountain High School, is the sole member of his school's sumo club. To participate in competitions, he attempts to recruit more members. Thanks to his enthusiasm and sincerity, four others join: Kaoru Kiyokawa, the judo team captain; Takayuki Kannai, a pro wrestler; Nanno Ippei, a skinny wannabe thug; and Raiden Goro, a giant but very shy person who is also an expert Go player. The five train together and later compete against a professional sumo club.