You should know this already Kyle...All girls are sluts! Seriously though, in my experiences, even "nice" girls will do this. I don't like to classify women anymore because even the "best" and "classiest" women will do sluty things if a guy has the right moves. It can be a hard thing to grasp.
You're right though, not ALL women will do this. BUT thinking that women won't because they have "class" is a faulty line of thinking. ANY woman will sleep with a guy the FIRST night they meet him, or immediately after they break up with their boyfriend, if the guy is skilled enough in seduction. Our socialization tells us otherwise, and that's why it's so hard for men to grasp, but I've experienced it many times. Even with what all the guys think are the "classiest" women.