Notice How Others React To His "Jokes"
This particular sleaze loved joking about just how funny it would be to toss certain people in the trunk of his car, beat them unconscious, and rape their comatose bodies. If/when Clark laughed at those jokes, it wasn't because he thinks rape is funny; it's because he assumes the speaker is, like him, the furthest thing from a rapist imaginable. That's the joke, right?
To be clear, rape jokes can be really funny if done right. I'm not about to say that anyone who makes those jokes is secretly pro-rape. I am saying that people who are pro-rape sure do like their rape jokes. The fact that it makes the target uncomfortable is part of the thrill -- it's a power play.
Some people use humor to target and isolate people, like a scraggly hyena that knows the only way it's going to get a gazelle is if it manages to separate it from the herd. In cases like these, nobody wants to be the humorless buzzkill -- the jokester can actually play victim because the offended ruined the mood. ("Oh, that's not funny? Then maybe you could explain to me why other people were laughing.") Maybe he can even talk her into meeting up later so he can "apologize."
So if a friend tells you that some guy's humor makes her feel uncomfortable, no matter how funny you think he is, maybe don't laugh at his jokes about raping and killing her. Even if she doesn't actually tell you that, maybe take notice if she's the only one in the room not laughing at the joke, and don't just interpret that as her being outvoted.