One day, Yuutarou, who lives alone, meets a married woman, Ai, at a local izakaya. After a falling out with her husband, she ends up drinking with him at the same table as him... This leads to them becoming closer, and before long they are physically intimate. Yuutarou gives Ai a spare key to his house, and Ai also starts heading over to Yuutarou's house with a shopping bag in hand when her husband goes to work. To ease the loneliness of their misunderstanding, the two begin spending intimate time together in the younger man's room...