Yumiko Sakura is a 50-year-old housewife. She has been married for 25 years, has two sons with her husband, and has lived a life of luxury, but her sex life with her husband has become completely cold. "Not only is there no sex... my husband feels like I'm just a roommate. But I guess that's what being a 'family' means..." She has had affairs before. She still can't forget the extraordinary night she spent at a happening bar she went to for the first time more than 10 years ago, when a friend invited her. "I was scared at first, but the atmosphere, or the excitement... I was so excited I wondered if it was really me." She wanted to experience that excitement and pleasure again...