Shizuko Matsuzaki is a 50-year-old housewife, an ordinary woman who has supported her husband and son as a devoted homemaker. Her daily life had always been peaceful—until one day, her husband suddenly announced an overseas business trip. Though she maintained a strong front, once he left the house, Shizuko began trembling with loneliness. Never one to suspect her husband before, she now found herself secretly fearing he might be unfaithful. Burdened by these emotions, she began touching herself in solitude, only to be discovered by her son, Nobuo. Unable to hide his shock and confusion, Nobuo listens as Shizuko confesses her inner turmoil. In response, he declares he wants to take his father's place and comfort his mother's body. Where family bonds meet emotional emptiness, a heartbreaking story begins.