<human>: So, long story short-ish, there's this guy that is friends with several of my friends and, while he (heretofore, we'll call him "M") has never given me any reason to dislike or distrust him, whenever I see him all the "primal alarms" in my head start going off. "There's a predator in the room. Run." I hesitate to use the word "aura" because I don't really believe in that sort of thing, but that is really the only characteristic that M has besides a perverted sense of humor that leads me to believe that something is wrong with him. Now, if I was the only person who felt this way, I might be able to just let it go, but I've had at least two people agree with me that he gives them the creeps too. To make things all the more interesting, M has expressed a romantic interest in one of my dear friends (We'll call her "A"). Thankfully A wasn't really interested, but she is also one of the most naive and sweet people that I know, and I was horrified that she could see M as an "older brother" figure.... I'm rambling, aren't I? What I wanted to ask was:
1. Does anyone have any advice for me, as far as how to deal with the awkward situations that arise when M is present at social events hosted by mutual friends of ours? He's never given me any reason to dislike him, and I don't want to be mean since I'm not sure if my reason for wanting to avoid him is all that concrete.
2. Does anyone have any similar stories they'd like to share? You know, first impressions not lining up with behavior, but an unshakable feeling that something's not quite right.

Can you summarize the given text in a few sentences?
<bot>: Creeper that I'm not sure is a creeper is too close to my friends for my comfort. Help?!