This facility is the only one in Japan that treats prisoners with ejaculation addiction. The inmates are those whose excessive sexual desires have disrupted their daily lives. This is a three-year record of O, a beautiful female prison guard who works there, from her rookie days to the present. "I myself will provide sexual services for the inmates," she says, with a professional attitude that never reveals her emotions while on duty. With prisoners who cannot control their impulsive sexual desires, the female guard coldly and condescendingly performs cowgirl sex as a matter of business, and even when the prisoners make them cum as they please, including sudden penetration, thrusting, and fingering, the guard never changes her expression. Even when she climaxes, she doesn't show it on her face. Instead of making a sound when she feels pleasure, she blows the whistle.