Four years ago, Chisato Nakajima married Hideo. At the time, Chisato was remarrying, while Hideo was entering his first marriage. Initially, they lived with Hideo's father, but after his passing last year, the couple has been living alone together. Chisato desires children, and Hideo shares the same interest, so their marital intimacy occurs frequently—every morning and night. Their relationship is harmonious and loving. However, one day, Hideo invites a man named Minegishi into their home. Minegishi Saburo... in reality, he is Chisato's former husband.