Previously, Miu had dated many men, but the current man is the one she truly likes. Today, they went to a hot spring together while Yuta's wife was away on a business trip. Miu was extremely happy to travel for the first time with the person she likes. They were joyful and laughing in the car, and when they arrived at the inn, Miu couldn't resist and immediately had sex. As it was Miu's birthday, Yuta gave her an anklet. Miu experienced a very happy time with her lover. That night, when she read the message from Yuta and his wife, Miu understood that men who cheat will always talk about divorcing their wives but they don't really want to. For a man, it's just a day of cheating. But for women, they will remember this day for the rest of their lives. She herself will never forget the most wonderful and saddest night of her life...