Jailbait Babysitter (1977)

Seventeen-year-old Vicki is nicknamed "Jailbait" by her older friends. Her boyfriend Robert grows frustrated that Vicki won't go all the way, though he's willing to wait. When a party spirals out of control, Vicki escapes with Lorraine's help, and Lorraine takes her in as a houseguest. As Lorraine teaches Vicki proper etiquette, Robert is left wondering what became of his girlfriend. Before long, Vicki discovers more about Lorraine's work as an "executive liaison."