Shougo Hayakawa arrives as a temporary student-teacher in Kana Orikura's class, simultaneously becoming a tenant in her household. He occupies the room previously rented by her long-distance boyfriend, Yoshihiko. As a distant relative—a cousin to Kana's deceased father—Shougo bears a striking resemblance to him, intensifying his presence in her life.

His proximity strains Kana's relationship with Yoshihiko, as she wrestles with loneliness and doubts about Yoshihiko's commitment, while developing feelings for Shougo. This positions Shougo as a direct romantic challenger. He confronts Yoshihiko about neglecting Kana, warning him that continued inattention risks losing her to another. This confrontation fuels ambiguity around Shougo’s true motives: whether he desires Kana romantically or merely acts as a catalyst to test her existing relationship.

Shougo functions as a disruptive force, compelling Kana and Yoshihiko to confront vulnerabilities in their bond caused by distance and poor communication. The tension revolves around whether Kana will remain loyal to Yoshihiko or pursue Shougo, complicated by their constant closeness and his resemblance to her late father, which adds psychological depth to her attraction.