A beautiful "special student undercover cop" attends a prestigious high school in order to bust up a student prostitution ring in this sexy spoof of the popular Yo-Yo Girl Cop series. Saki (Mihiro) may look like you're average innocent schoolgirl, but in reality she's a highly skilled agent for the Japanese government. Armed with a lethal yo-yo and a special pair of see through underwear, Saki befriends a student prostitute named Asuka in hopes of identifying of the ringleaders and gathering the evidence that will bring them to justice. Accomplishing that goal is no simple task, however, because in addition to being bullied about her unconventional undergarments, Saki soon finds herself falling for handsome young classmate Takuya. Now torn between love and duty, Saki is shocked to learn that Asuka has been murdered after her double life was discovered, and that the leaders of the prostitution are none other than the Headmaster of the school and a highly respected teacher.