Naoki Watarase, a high school teacher overseeing homeroom for students Kadode Koyama and Ouran Nakagawa, exudes a laid-back charm through his square-framed glasses and weary gaze, softening traditional hierarchies with his approachable presence. His demeanor blends approachable warmth with a wry, critical edge, fostering candid dialogues with students interspersed with biting observations. While navigating romantic attention from pupils like Kadode, he upholds a professional distance, addressing their affections with measured maturity.

Before his class’s graduation, Naoki sustained a years-long relationship with Hikari Sumaru, a former classmate, which lingered as a relic of routine rather than genuine connection—a testament to his emotional inertia. Post-graduation, he discloses the dissolution of this stagnant bond, marking a conscious pivot toward self-reinvention. This shift aligns with Kadode’s transient romantic overtures, their unresolved dynamic left open-ended.

His narrative arc traces a journey from passive endurance to purposeful transformation, catalyzed by mentorship responsibilities and the severing of hollow ties. Beyond his classroom role, specifics of his personal history remain undisclosed, anchoring focus to his evolution within the documented timeline.