Yui, who runs a massage parlor with her husband, finds their sex life bland. One day, while giving a massage, she can't help but be captivated by a client's erect penis and ends up having sex with him. Having tasted the forbidden fruit, Yui starts secretly providing lewd services to her clients. Word spreads, and more clients come in for H-type treatments one after another. The lascivious little devil, Yui.
