Gonji Abe, known as Gon, is a physically sturdy boy who leads a group of male classmates. He shares a childhood friendship with Akira Yanagisawa, the class deputy. Gon possesses a strong-willed personality that significantly impacts group decisions and actions.

He participates in an undisclosed incident with other boys, leading to disciplinary action that cancels the class's participation in a regional choir competition. Following this event, Gon takes personal accountability, strongly advocating for the class's reinstatement. He successfully persuades Akira to negotiate with school authorities.

His involvement in the incident results in an abrupt mid-year transfer to another school. Despite his departure, Gon's advocacy for the choir competition leaves a lasting impression. It motivates his former classmates and their teacher to dedicate their competition performance to his memory and that of Shizu Miyanaga, another departed student.

Gon's background beyond school life and friendships remains undocumented. His character arc focuses on his peer group role, the repercussions of collective actions, and his indirect influence on the class's perseverance after his exit.