A confinement room known as the "pigsty" exists in this town. A black gyaru who once took pride in her beauty and body is suddenly captured and taken there. Her naked body is bound and suspended in midair, tormented by a vibrator while being sexually abused. Forced into a quadrupedal restraint, her body is repeatedly penetrated by one man after another in a continuous creampie gangbang. Gradually transforming into a "sow" immersed in pleasure, her mind consumed solely by the desire for male cocks, her training progresses without end.