Katsuto Masuoka

Masuoka receives little characterization beyond his participation in high-school competition. The series does not provide enough information about his private life or motivations for a detailed personality profile.

Masuoka is a competitive karuta player participating at the national high-school level. Reaching the Omi Jingu tournament places him within a field assembled from strong school programs across Japan.

No specific class rank, distinctive playing style or exceptional sensory ability is firmly established for him.

Masuoka appears during the national championship storyline, where the number of schools and players surrounding Mizusawa expands considerably.

He is present through several stages of the tournament, but the narrative does not build a major individual match or continuing rivalry around him.

Chihaya Ayase, Taichi Mashima and their Mizusawa teammates compete within the same national high-school tournament field as Masuoka, though no substantial personal relationship with him is established.