Rio is a serious office worker by day, but secretly works at a men's massage spa. When a coworker happens to visit and discovers her double life, he uses the secret to force increasingly sexual services from her. Her soft, voluptuous body and obedient attention only fuel his demands. Soon he is fucking her whenever he calls—in the office, at the spa, or in the changing room—until the J-cup beauty becomes his on-demand massage girl, used for sex and ejaculation whenever he wants.