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1975 Toei movie.

Miss Yamagami is beautiful with a willowy figure and slender legs. She seems out of place teaching in an all boys school. The young school marm is fully aware of her power over the impressionable boys in school and it satisfies her vanity. She stirs up their nameless longings until they are carried away and resort to acts on which Miss Yamagami had not counted on.

Investigative reporter Hayakawa Junko visits a town that was once the scene of a scandal involving mass prostitution to cover the activities of high school girls at motels. What Junko sees there is a flood of sexual promiscuity among high school girls that is even more shocking than what has been reported in the media. During her investigation, Junko hears a rumor that it is a "high school version of Romeo and Juliet," in which two high school students, Ryuichi and Yuki, fell in love but their families opposed their relationship, so they cut off each other's little fingers.