Go Kato is the lead singer of the emerging rock band Bee Hive and a university student. He lives with his younger brother, Hashizo, in a small apartment after the boy lost both parents as a baby, leaving Go as his primary guardian. Physically, Go is characterized by his brown eyes and neck-length blonde hair.

In terms of personality, Go is depicted as cocky yet charming, possessing a natural charisma that suits his role as a frontman. Before his romantic involvement with the protagonist Yaeko "Yakko" Mitamura, he had a reputation as a playboy. However, his character undergoes a significant shift when he falls in love with Yakko; he becomes totally devoted to her, shedding his previous flirtatious demeanor in favor of a committed relationship.

Go's primary motivation is to achieve professional success as a musician, a goal he pursues with clear dedication. His role in the story is centrally defined by the tension between his ambition to make it in the music industry and the demands of his personal life, specifically his romance with Yakko and his responsibility for Hashizo. He often struggles to balance these competing priorities, which creates much of the narrative conflict.

His key relationships define his character arc. He is the older brother and caretaker of Hashizo, a responsibility he assumes full-time. His romantic relationship with Yakko begins after she enters his life through an encounter with Hashizo, and it is through this relationship that his character develops from a carefree playboy into a devoted partner. He also shares a friendship and band membership with Satomi Okawa, which forms a central part of his social and professional world.

Go's notable abilities stem from his role as a musician. As the lead singer of Bee Hive, his voice and stage presence are his primary talents, and much of his character's actions revolve around performing and pursuing his musical career.