Masaki Oono

Oono receives little individual characterization. His appearances are tied to school competition and the circumstances surrounding Arata at the national tournament.

The established material does not provide enough information about his life away from the tournament for a more detailed personality profile.

Oono participates in competitive high-school karuta. His involvement at the national championship places him among players representing Fukui at Omi Jingu.

No specific class rank or specialist playing technique is firmly established for him.

Oono appears during the national team championship as the narrative follows Arata outside Mizusawa's matches.

Arata enters a team match despite not being legitimately registered as a member of the participating school, an action that subsequently creates a disciplinary problem when it is discovered. Oono belongs to the group surrounding that incident.

Arata Wataya encounters Oono through the Fukui team competing at the national high-school championship.

Shouji Kawauchi is another Fukui-area player appearing around the same national tournament storyline.