Andrea and Amy are prostitutes who also somewhat serve as a sex therapist and her assistant (respectively) for their clients. Through flashbacks of previous clients and of random couples, they introduce new female client Joy into the pleasures of sex.
Joy
Amy
Andrea
Joy's Friend
Joy's Neighbor
Joy's Friend's Girlfriend
Amy's Flashback Lover
Domination Client
Man in Threesome
Neighbor's Lover
Final Client
Joy's Friend's Lover (uncredited)