Fitch, NIKUYOKU label exclusive actress Tsukada Shiori shows off her plump, busty, big-assed body in an impossible-angle high-cut swimsuit that's just like something out of an erotic manga (it's spilling out everywhere!) and gives an obscenely seductive lesson! Shiori-sensei is plain but earnest, and has a good reputation among those around her, but behind the scenes she's a sex-crazed monster who preys on fellow teachers and students! She has an exhibitionist habit, and while she keeps a cool face, she actually enjoys wearing perverted swimsuits underneath her clothes. One day after school, Shiori warns a male student who is trying to steal a female student's recorder. If he's that interested in girls, she shows him the perverted swimsuit she was wearing underneath her clothes, exciting him...