Nozomi is an older sister who has a younger sister, Kie with mental disability and has not revealed Kie’s existence to her lover, Takashi. One day, Takashi gets confused when he was informed of Kie when he proposes to her. From there, they face one after another the worries peculiar to her family with disability, despairing in her life far from "normal", and she tries to give up her marriage to Takashi. However, something happens which made her reconsider her own life.