Rinko is a run-of-the-mill office lady who deals with her everyday stress by pickpocketing and shoplifting. One day, a failed attempt to take advantage of a peculiarly aggressive molester on a train results in her sudden arrest, after which she's promptly imprisoned to "atone" for her misdeeds. With a clean, spacious cell to herself and a handsome guard watching over her, Rinko's new prison environment doesn't seem all that bad that is, until her "atonement" begins...