Buffy is the evil spoiled upper-class heroine of this movie. Jaded beyond belief, she makes a deal with her step brother to seduce and humiliate people who cross their path.
She makes a bet that he can't seduce the headmaster's daughter, who has just come out in a magazine as the "virgin until marriage."
If the step-brother can't do it, she gets to keep his very expensive car.
If he can seduce the virgin, she promises to sleep with him.
Sordid enough for you yet?
It's just terrible, evil and sexy.
The setting is ultra-rich Manhattan, which lends a beautiful background to this very unhealthy and seductive movie.
If you want to be bad, this is the movie for you.