June Gotou is a married woman who, along with her husband, has been so busy working hard that they've barely had time for hobbies or quality time together. Longing to feel the excitement and butterflies she once felt when she first met her husband, she turns to an affair website. Meanwhile, Amina Nanjou notices her relationship with her husband growing distant after childbirth. When her child was young, their couple time was dedicated entirely to parenting, but as the child grows older, they find themselves alone together more often—and realize they've become sexually incompatible. These shifting emotional states lead both women down separate paths toward extramarital desire.