A beautiful older sister, Murakami Ryoko, and her younger brother are sent to prison for killing the son of a powerful man. Even though he knows that Ryoko is innocent, the corrupt prison warden uses his authority to impose harsh punishments on her. He forcefully tortures her pussy under the guise of a physical examination, and ties her up and down in the correctional punishment cell for corporal punishment. In the end, he forcibly injects an aphrodisiac into her and takes her to his brother, who then takes her in front of Ryoko, forcing her to have sex with him in a humiliating incestuous sex scene between siblings! Even though he knows it's wrong, his body craves pleasure and he reaches orgasm with a painful cry, cumming inside her!