Nanami lives with her mother and leads a married life at her parents' home. Lately, she has been feeling distant from her husband due to his work neglecting the family. Her sister Keiko returns home with her husband Tetsu. After dinner, Nanami finds herself alone with Tetsu and ends up venting about her husband's behavior. However, Tetsu is also struggling with their strained relationship... As they find common ground in their troubles, the two draw closer, unable to suppress their desires, and fall into a W-affair.
