Guys who have to be "alpha" in ever situation.
Dated a guy like that. Any sort of social interaction, he had to go around to each guy and had a "system" to stare them down "into submission."
Seriously. BBQ with friends. Walks up to the guy on grill and starts demeaning his cooking. Then attempts to be taller and just stares at him. Then walks over to me triumphantly, "That guy knows his place in the hierarchy now. You're with the most alpha guy at this party."
That relationship didn't last long. "Any man who must say I am king is no true king."
Edit: Since multiple people are asking, we got together because a few of my friends recommended him. I think it was one of those situations where they didn't know what he was like because they weren't dating him and had known him since they were little kids, so probably had memories from way back that helped them overlook the douche-ness. I didn't have any such fond memories to keep me going so that crashed and burned real quick.
And yes I know it was still a terrible mistake. I took a break from dating after that.