38-year-old Reiko Shimura, divorced after nine years of marriage, is now enjoying her single life. One day, attending a reunion with her former classmates, she decides to embrace mature sex to rediscover the joy of being a woman. In this moment where long-awaited encounters and adult allure intertwine, she discovers a new version of herself. Amidst pure memories of her school days and the clash of adult desires, her heart and body awaken to fresh excitement.