In "Chuuken Kunshu," Katou is a member of the high school swim club whose daily life is disrupted by Matsuoka's frequent visits to deliver lunch and release pent-up stress by playfully punching him. Katou, moved by Matsuoka's actions and caught up in the moment, confesses his feelings, describing Matsuoka as "cute" with a shy smile. However, Matsuoka's response is characteristic of a tsundere, leaving Katou's affections in a state of uncertainty as he grapples with lingering doubts about their relationship.
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