44-year-old Matsuoka Mutsumi is a mother of one who supports her household through knitting piecework. The word "demure" perfectly describes her. She has lived a pure life, having had almost no exposure to anything erotic. She met her husband at 27 and married the following year. After becoming pregnant, her marital relationship faded, and she hasn't had sex since—zero encounters. With no experience of infidelity, her total number of sexual experiences in life amounts to only five times. Having gone roughly 16 years without pleasure and nearly forgotten what it feels like, she refuses to let her life as a woman end this way. Determined to embark on a new challenge, this near-virgin wife sets out on an adventure to discover the joys of womanhood through her first-time experience.