To repay her brother's debt, the sister is kidnapped and held captive in the home of an insatiable yakuza man, forced into relentless sexual servitude. For ten days, she becomes his personal sex slave—her body available whenever he desires. The moment he wants sex, she must immediately present her ass. Anytime, anywhere, penetration happens on the spot, followed by creampie after creampie, plunging her into days filled with overwhelming pleasure. Her lustful body grows increasingly aroused, unable to calm down. With each forced penetration, her body melts further into depravity. A truly yakuza-style prison of perversion awaits.