Weeding out the ones who only want to get laid
I’ve found many, many fewer of these men in real, adult life than I was raised to believe I would find. (See Bullish Life: Let’s All Just Agree on Some Basic Principles of Sexual Ethics.)
That said, I don’t think there’s all that much magic to weeding out these men besides not sleeping with the guy until he’s put in more effort than a person would put in just to get laid. Make sure to ask him where he sees himself in five years. If he’s a total psychopath, none of this will stop him, but if he’s only willing to dissemble so much, you can dissuade a casual-fuck-that’s-no-good-for-you by making it clear that you are assessing him as a good prospect for the future.
Bonus move: Do you have a brother? In town? Ideally, a large older brother, but in a pinch a cousin or sister or tiny brother will do. So: Introducing a guy to your parents before you’ve slept with him is basically insane in our culture, but if you have a family member in your age group, you could certainly arrange a fourth-date group outing (a band everyone likes, a Groupon deal at a restaurant…) that includes you, your date, your brother, and several other people.
It’s harder for a dude (especially one who’s been on 4+ dates with you) to see you as just a piece of ass once he’s met any member of your family (other than another hot girl, in which case such a dude may just see your whole family as a hot-piece-of-ass factory). No man wants to run into another man on the subway and be like, “Oh, you’re that dude I sat next to for two hours at that sushi place. I just wanted to bang your sister and never call her again.”
On the topic of nerds
I am engaged to a man who plays Dungeons and Dragons, which I have discovered is basically code for “I have a close group of friends and we all have impressive vocabularies and know a lot about world mythology.”
Personally, I have been known to ruin people’s parties by doing math tricks, and I don’t want to accidentally commit myself to someone who is going to want to get cable television in our home and then also watch sporting events on it. So I can hardly complain that our wedding ceremony will probably be conducted at least partially in Elvish. Sounds romantic, really. Elves have pretty hair.
A guy who gives a long monologue on Game of Thrones might just be nervous. Since you’ve been kind of writing those guys off anyway, might as well try, “That show looked fun, but it turns out to have kind of a lot of rape in it, which I found … distracting.” (Not to foist my impression of Game of Thrones on you, but that was totally my impression of Game of Thrones.) See where that goes. Either you can truly write the guy off for saying something idiotic, or maybe you’ll end up in a fascinating discussion about why fantasy, as an industry, could use more diverse voices.