Experiment In Terror by Lizbeth Dusseau

Rachel Linney's college reunion is a real drag - until she unwittingly stumbles on the guest of honor, a high-powered Hollywood attorney Jackson Brandt who develops an instant fascination for the lovely college professor. A little investigation into her life reveals that Rachel writes nasty sadomasochistic sex books under the penname Marilyn Hayworth. When Jackson surprises her with his discovery, she's furious that he would dare pry into her life. But then he makes a startling offer; proposing to make her kinky fantasies come to life. Rachel is so captivated by this mesmerizing dominant, that she finds herself swept into his S&M world. Jackson delights in snatching Rachel from her modest life, dressing her like a whore and thrusting her into sexual situations, where she experiences the bondage, punishment and humiliation she writes about in graphic detail. She's whipped in an infamous NYC sex club, gangbanged by three black men, and subjected to humiliating public exposure....