"I created Buffy the Vampire Slayer as a movie, long time ago, to protect, as i’ve said before, the “blonde girl in the alley who always got killed.” One of the distinguishing features of the “blonde girl in the alley who always got killed” was that she actually had sex. She always seemed to be punished for it. That bothered me. I thought it wasn’t fair, so, Buffy was created as a sort of stereotype buster on that level."
Joss Whedon, Buffy the Vampire Slayer (Innocence Commentary)