30-year-old Masaki Minami. A married woman in her fifth year of marriage, working as an office clerk. Her total number of sexual partners, including her husband, is four. The previous three were boyfriends from middle school, high school, and college. When it comes to experience, she and her husband are in a similar situation—neither knows if they're particularly good or bad. Minami enjoys watching AVs, studying them, and trying out what she learns, taking pleasure in satisfying her partner. She has an intense curiosity about sex and a strong interest in adult videos. Driven by a desire to discover her own limits, she's determined to reach orgasm today. A serious and pure, untouched body is about to open Pandora's box.