In a coastal town in Niigata Prefecture, Japan, high school senior Kayako Kirishima feels lonely and uncertain about her future as she prepares for college. One day in class, she meets Masami Endo, a quiet girl ostracized by other students because she had an abortion. Despite the social stigma, Kayako is drawn to Masami, and the two quickly form a close friendship. As they spend time together, their bond deepens into romantic love, but both struggle to understand and articulate their feelings in a world that offers them no language for it.

Kayako is introspective and reserved, while Masami carries the weight of her past trauma and the judgment of her peers. Their relationship unfolds in quiet, everyday moments — walks by the sea, shared cigarettes, and long silences filled with unspoken emotion. The story uses minimalist, realistic artwork and muted panel layouts to emphasize subtle shifts in mood and connection.

The narrative arc follows the tentative growth of their romance, punctuated by a crisis when Masami visits a former lover during summer vacation. She lies about where she has been, and Kayako, hurt by the deception, confronts her. They reconcile after Masami admits the truth, but the incident reveals the fragility of their relationship. Eventually, they must decide on their futures: Kayako chooses to move to Tokyo to pursue an art career, while Masami opts to stay in their hometown and work a modest job. The manga closes with Kayako departing on a train, Masami watching from the platform, their love unresolved but deeply felt.

The story does not rely on melodrama or expressionistic art; instead, it achieves emotional resonance through understatement, realistic dialogue, and the careful use of negative space. It explores themes of loneliness, societal judgment, queer awakening, and the bittersweet inevitability of parting.