Hentai - Kyonyuu Kazoku Saimin

An important and respected Tokyo industrialist named Kasama hires Kyoko and Sugita, two young and eager detectives, to find his missing daughter. The few clues he is able to give them reveal that the missing girl had recently made friends with an unsavory group of people, one of whom appears to be connected with a powerful and mysterious nightclub owner called Takami. Kyoko, a brave and lovely girl, goes to work for Takami in order to learn more about his organization, even though he forces her to submit to his passionate advances and eventually delivers her to a special client for peculiar sexual experiments. She and Sugita gradually learn that Takami operates a large narcotics ring headed by an unknown "Big Boss" who always appears masked, that together they abduct pretty young girls, addict them to heroin, rape them and put them to work as prostitutes. One of these seduced and addicted girls, she discovers, is Kasama's missing daughter. With the help of an international narcotics agent, Kyoko manages to escape from Takami and his goons, and while the Tokyo police track down and arrest the members of the gang, she and Sugita rip the mask of respectability from the brutal "Big Boss' - Kasama, their prominent client. To his utter horror, this ruined man learns that he has unknowingly raped, drugged, and prostituted his own child. Hentai is not a pretty story, but neither is the condition of Kasama's beloved daughter when she is finally returned to him, her body ravaged and her mind destroyed by her father's abnormal lusts.