Insatiable (1980)

from imdb

An orphaned heiress/fashion model embarks on a series of sexual encounters to satisfy her loneliness and insatiable appetite for sex. Marilyn Chambers plays heiress, model and actress Sandra Chase. She feels she is not sexually fulfilled. Her agent played by Jessie St James gets her a role in a new movie. She has encounters with Serena, and Richard Pacheo. She also tells a flashback story of her being devirginized by David Morris. She also has a fantasy encounter with Mike Ranger, Morris, and St James. She also has a fantasy encounter with John Holmes. St James and John Leslie get intimate in the film also