Why do you not embed? Are you on your phone?
Anyway, tragic. For those who think he's "creepy," how SHOULD he have approached her? If the answer isn't "Guys like him just don't get to have parties?"
Okay, probably not the random ass thrusts. However, I guarantee you he learned it from other men and the women who allow it. People will shame him for randomly grinding on her. And in the real world, yes, that's bad. But that's how parties are, and if you don't know that, you've never been to a party.
But then, if parties are magical places where you can grab and air-fuck people at random, they must also be places where you can refused to be air-fucked, because you only want attractive people to air-fuck you.
In summary, Chad has it good. A normal life, or worse, for this guy.