In the past, Miu had dated many men, but the man she is with now is the one she truly likes. Today, they both went to a hot spring because Yuta's wife was on a business trip. Miu was extremely happy to travel for the first time with someone she likes. They chatted and laughed happily from the car, and when they arrived at the inn, Miu couldn't hold back anymore and immediately jumped into intimacy. Since today is also Miu's birthday, Yuta gave her an anklet as a gift. Miu spent incredibly happy moments with her lover. That night, after reading a message from Yuta and his wife, Miu realized that when men cheat, they will always talk about getting a divorce with their wives, but they really don't want that. For a man, it’s just a day of cheating. But for a woman, she will remember this day for a lifetime. She herself will never forget this most wonderful yet saddest night for the rest of her life...