Aika Nagano is a devoted wife married to a successful entrepreneur. Their life is going well, and they are planning to start trying for a child. However, one of her husband's female employees collapses from overwork. The couple visits the woman's home to apologize, where her husband laments that he can no longer make love to his wife. Moved by his sorrow, Aika decides to offer her own body to him. This decision drastically changes the course of their lives.