Koume has been married for three years. She and her husband were childhood friends, and they have known each other since childhood, but they have both grown up and gone on to live their own lives. Then, one day, she happens to meet him again, and they get excited talking about old times, which leads to a relationship that develops into marriage. However, she discovers that her husband has a habit of cheating, and communication between the couple decreases significantly. To relieve her loneliness, she begins to enjoy time with other men using a dating app. She then meets a man there, with whom she has perfect physical compatibility, and they end up going on a trip together...