Gou Hiromichi is a senior at St. Ishiyama High School and a prominent member of the Rokkesei, the group of the six strongest students at the school. He is known for being the most violent member of the student body, a reputation that excludes the transfer students from Ishiyama. In terms of appearance, he has maroon hair cut to ear length and black eyes. Beyond his combative pursuits, he is also a participant in the Amateur Radio Club and the International Amateur ARDF Contest.

His personality is defined by a ruthless nature and an active, nearly impulsive, desire to seek out fights. This violent impulse was clearly demonstrated when Mikki stated that Tatsumi Oga was the strongest among those present for a rooftop confrontation; upon hearing this, Gou immediately attacked on instinct, seeking to challenge the perceived strongest opponent. This advance was intercepted by Shintarou Natsume, leading to a reasonably matched fight between the two. His primary motivation revolves around combat and proving his strength. Regarding his role in the story and his relationships, his key interaction is with Shintarou Natsume, who serves as his rival during the conflict on the school rooftop. Information on his background prior to the events at St. Ishiyama High School is not detailed. As for notable abilities, he is suggested to be extremely fast, with a speed that can make him nearly imperceptible to his enemies. There is no available information regarding any significant character development or arc he may undergo.