Aoi lives with her husband, who requires care after an accident, and her father-in-law, who suffers from a chronic seizure condition. Her father-in-law, not wanting to worry the family, always pretends to be in good health. One day, he accidentally witnesses Aoi engaging in sexual activity with her husband, stirring up complex emotions within him. That night, the father-in-law suddenly suffers a seizure, and Aoi's relationship with him takes an unexpected turn.