After losing her father in an accident, the beautiful mature woman Hara Chitose lives alone with her mother. One day, her brother Takeshi's wife, Maki Hojo, arrives, triggering an event that shakes the family's bonds. Takeshi's business is failing, and Maki has come with the intention of manipulating Chitose into writing a will favorable to them, even as her mother's health deteriorates. But Chitose becomes more interested in satisfying her own desires than in the inheritance. Maki, using her body as a tool of seduction, introduces Chitose to the pleasures of lesbian intimacy. Their relationship descends into hidden lust within the family, leading toward a dark and buried secret.