Daiki is captivated by the visit of his wife's friend, Kaya, enchanted by her gentle demeanor. Unlike his usually strict wife, Yuka, he finds himself drawn to Kaya's warmth and kindness. When Yuka suddenly leaves for work, Daiki is left alone with Kaya, and the tension builds as they spend time together for the first time in a while. Unable to sleep, they decide to have a drink late at night, leading to a conversation that deepens into something more intimate. Listening to Kaya's personal struggles, their emotional bond grows stronger. With Yuka away, their closeness turns physical, and soon their lips meet. As new feelings awaken, their relationship takes an unexpected turn.