Mifuyu Fujisaki, 45, is a full-time housewife living in Tochigi Prefecture. She has been blessed with one son and one daughter, and this year marks the 20th year of her smooth-sailing marriage. At this turning point, Mifuyu looks back on her life and notices a change for the first time. In the past year, she has made love to her husband just a few times a year. And it seems she only remembers it when her husband is in a good mood... She no longer seeks it out herself. "It's not that I don't love my husband, but...stimulation? Simply put, I don't have enough stimulation..." She doesn't want a thrill, but she wants some excitement. She replaces her feelings of guilt with a sense of immorality, and her crotch gets wet during her first affair...