Build a movie plot around this: Who is Sebastian's friend in the movie? Kathryn
A:
New York City. 1999. The womanizing Sebastian Valmont (Ryan Phillippe) is with his therapist Dr. Greenbaum (Swoosie Kurtz) to talk with her over his sexual urges over other women. Sebastian decides that he is more or less cured and bids goodbye to him to set out as a new man. She thinks she has convinced him of sustaining longer and more serious relationships with girls. After Sebastian leaves her office, Dr. Greenbaum gets a phone call from her distraught daughter Marci (Tara Reid) who claims that her boyfriend just broke up with her and posted a nude photograph of her on the Internet. Dr. Greenbaum realizes that Sebastian is the guy whom Marci is talking about and she chases after him and yells at him for violating and corrupting her daughter in front of a small crowd. Sebastian slyly denies knowing who Dr. Greenbaum is and leaves, only stopping to pick up another young woman.Kathryn Merteuil (Sarah Michelle Gellar), the image of social perfection, takes the sheltered and naive Cecile Caldwell (Selma Blair), under her wing, promising to turn Cecile into a model student like herself. Kathryn's real intention, however, is to take revenge on Court Reynolds, Kathryn's own ex-lover, who dumped her for the "innocent little twit", Cecile. Kathryn intends to corrupt Cecile by getting her to sleep with as many men as possible, thereby destroying her reputation and teaching Court a lesson.Kathryn asks for help from her step-brother, who happens to be Sebastian. Though Kathryn and Sebastian have collaborated in schemes of manipulation before, he initially refuses. He is busy planning another "conquest", the beautiful Annette Hargrove (Reese Witherspoon), a girl who has published a manifesto saying that she plans to keep her virginity intact until she gets married. Annette is the only daughter of the new headmaster at their prep school Manchester, which is currently closed for the summer season. Sebastian learns that Annette will be staying with his aunt Helen Rosemond (Louise Fletcher) in the Hamptons on Long Island...