A teacher, Sakiko Kurata (Yuki Kazamatsuri), receives a phone call regarding one of her former students. Young Sueko (Ayako Ota) is accused of being a prostitute and has requested Sakiko's help. This minx seduces random strangers for sex, but does not ask for payment. Sakiko has moved to another town and barely remembers Sueko, but there's something about her that awakens painful memories of her own secretive past. What is that strange paint thinner smell on Sueko? Who is the man in the nylon ski mask that violently assaulted Sakiko many years ago? In her search for answers, Sakiko discovers that her past may have inadvertently destroyed another family's future. The "lusty schoolmistress" provided an obvious fantasy figure for Nikkatsu Roman Porno scenarios. There were at least a dozen films made with the FEMALE TEACHER banner, each pitting a plethora of pert young cuties against their more mature and experienced classroom rivals. FEMALE TEACHER: DIRTY AFTERNOON is one of the best, and most controversial, of this series of films.