I wanna give my 2 cents because I got called creepy a few times last year, when I was pushing my boundaries. Lately I get called sexy, hot, or cute, not creepy; I haven't been called creepy in almost a year. I haven't changed much, visually.
You're creepy if you don't think the woman will enjoy it... Picture a guy fondling a tied up woman's boob, knowing that the woman is feeling revulsion. That's creepy.
A creepy guy would "take advantage" of a passed out girl, getting pleasure without regard to how the woman feels at all. (Not that most guys who get called creepy are actually creeps.)
When you hear "creep", think "pervert". Not the lovable kind who is fun, but the leery kind by whom you don't feel respected. The girls feel like "he really thinks I'm an object."
Imagine Gollum, but instead of the Ring, he wants sex. Then imagine him after he splits off into the nice version of himself... His creepiness is gone, cuz he's no longer plotting on how he can get the Ring from you.
You have to seem like you have other options, or at least like you won't get weird if rejected. A good looking guy can still be a stalker, and an ugly guy can have a pre-selected vibe.
Creepy = how likely the guy is to stalk her, to fall in one-sided love, etc.
So if you don't feel like the girl is attracted to you, you will behave that way...
I know a mother****er who looks like a FAT version of Zach Galificankaikas (sp)... Based on his looks, this guy should NOT get girls.
He's with hotties every time I see him, and I ran into him pulling a hot blonde from a bar one time (they were dancing sexually in the parking lot.) He's got mad game, he's very charming, and you can tell that he is not a social retard [in fact, you can tell he has a ton of friends.] He's not gonna kidnap you and put you in his trunk because you talked to another guy and he got jealous.
"Unpredictable" is good, but "unstable" is bad
Of course looks matter a lot, but think about it: Your clothes, your facial expressions, your state of health, your haircut, your grooming... They're all indicators of how socially in-tune you are, and how experienced you are with girls. So if a girl calls you creepy, it doesn't mean that she's insulting your body. It just means she's not impressed with the persona she saw.
Plus, the only times I've been called creepy are because I said or did something that was clearly socially uncalibrated... Acting in ways that I didn't feel entitled for. A guy who was super good looking would have had more reference experiences growing up, and would be more sexually comfortable and congruent. As I've gotten more experienced, I haven't gotten called creepy in almost a year. But I have been called sexy a lot, by strangers, around whom I probably would have behaved creepily a year ago.