Holding the belief that "all women should be brought to their knees," a group of men who have long treated women as research subjects now focus on a new theme: "Do women subjected to pleasure torture end up surrendering completely, mind and soul?" Their target is Rioa, a female detective who had been conducting an undercover investigation to prevent the destruction of the institute. Falling into a trap during her investigation, she is captured and subjected to various forms of torment. Humiliation and fear gradually transform into pleasure, and the female detective slowly descends into becoming a sex slave. Her body convulses violently through intense orgasms. Yet, has she truly surrendered deep within her heart?