Chisato has come to stay at her daughter's couple's house to help with housework because her daughter Yumiko has injured her leg. It was Chisato who devotedly supported Yumiko, but her son-in-law Shuta was looking at Chisato with more feelings than her mother-in-law. And it happened when Yumiko was sleeping. Shuta, who hadn't seen Yumiko since she was injured, hugged Chisato and kissed her. Chisato was hesitant about her son-in-law's unfaithful act, but her mind and body, which was lonely with her masked couple, gradually accepted Shuta.
