Sebastian Valmont is a major character of the teen drama, He is a minor antagonist and anti-hero of the movie. Cruel Intentions. He was played by Ryan Phillippe.
He just like his step-sister and villainess, Kathryn Merteuil, was born into the most noble, wealthy social class in New York City. His dad, a rich businessman and was born and raised at the Valmont House, and married a socialite and philanthropist, Tiffany Merteuil. In the process, he also met and became close to Kathryn, and became sexually promiscuous and many times slept with women, he didn't know, and kept record of all this in his journal. In the movie, she asks Valmont for help in Cecile's corruption.
At first he doesn't want any part of it despite joining forces with her in other plans of evil before and he is planning another scheme with heroine and high school student , Annette Hargrove , and the plan is this if he fucks her and gets her to lose her virginity then he gets to fuck Merteuil but if he loses then she gets and keeps his car. He agrees when she says he can put it anywhere. Then he has a rough time trying to have sex with Hargrove and she sees right through him and is able to resist him and has been told by Cecile's mom of his dark ways. He then joins Merteuil in her plan to corrupt Cecile.
He calls Cecile to his home and gives her a letter from Ronald and then blackmails her trys to have sex with her, which Merteuil encourages later. Then Valmont gets the hots for Hargrove, who while appreciating him still blocks him from fucking her. Then he calls her a hypocrite and after an emotional fight, she leaves his aunt's house and later they share their feelings. Then Kathryn the following day first she offers herself to Valmont, who refuses, and then later Merteuil doesn't want to fuck him and reveals she used him and knows he was in for real love with Hargrove and even though he may have won she got him to lose Hargrove and she doesn't fuck losers.
Then Valmont gives her his journal, which explains his evilness but at the same time his true feelings for Hargrove also. Then when Merteuil talks to Ronald about Valmont's affair with Cecile and that he abused her physically and then Ronald and Valmont fight, which Hargrove tries to stop the fight and is thrown in the way of a car coming but Valmont saves her by pushing her to where she is safe but he is killed and hit. Before he dies, he makes his profession of his love, which she accepts.