Kathryn is one of the premiere experts of manipulation. She enjoys destroying others. Her typical day consists of seduction, betrayal, and sex. Kathryn teaches the innocent Cecile how to french kiss a girl and about the joys of sex. When Annette the author of a magazine article about the virtues of virginity arrives she makes a wager with her step brother to determine Annette's fate. Kathryn bets "rear entry" intercourse against her step brother's car to motivate her step brother to seduce Annette. After Sebastian dies when a car strikes him she addresses her school about her brother's life. She is caught with drugs in her necklace cross and Annette circulates Sebastian's diary of Kathryn's misdeeds to the entire school.

Sebastian is the king of cool in this movie. He seduces women at will and no woman is too challenging for him. He brings the innocent Cecile over to the dark side just for fun. Sebastian even enters into a bet with his stepsister Kathryn to see if he can seduce the innocent miss virgin Annette Hargrove. He tries a variety of techniques and does make progress. The only problem is that once he is at the verge of success he starts to fall for her. Sebastian dies at the end of the movie when a car hits him after being distracted by Ronald whom he is fighting with.

Annette is a youthful idealist that believes one really should wait until you are married and in love before experiencing sex. She wrote an article in a teen magazine about her thoughts on this matter. Sebastian thinks her thinking is so ludicrous. Sebastian enters into a bet with his step sister to see if he can seduce Anette and wipe away her innocence.