Shihori is 38 years old. Since losing her husband, she's been overwhelmed with work and constantly exhausted, often dozing off in the living room. In her weary state, she finds herself masturbating while reminiscing about her late husband. Her son becomes aroused seeing her like this and one night, he sneaks in and touches her body. In the darkness, Shihori lets out lewd moans and instinctively reaches for her son's body. Their forbidden relationship gradually deepens, leading to increasingly intimate encounters between them.