The Promiscuous Sex (1967)

Liz is a young New York City model/prostitute who meets a good natured young man, named Michael, with whom she has a one-night stand. When Liz tries to help out her boss, Sam, with his business, it leads them to a vicious gangster whom wants Liz for himself, and she tries in a desperate move to get out of the business to try to make a life with Michael even though she knows it may never work out.