To answer your first question, it would depend why she's such a "creep magnet"...
If she has a certain attitude about guys that attracts creeps, that could be an issue. It wouldn't have anything to do with the fact that she attracts creeps, just her attitude about guys.
Similarly if she's the kind of girl who is paranoid and thinks all guys are creeps, that would also be an issue for me.
But if she's just a normal girl to me, who happens to attract creeps, then there's no issue.
As for what I would do when I'm dating her, obviously I wouldn't like it, just as I presume she would not. It wouldn't stop me from dating her or be a deal breaker, although I would try to help her by trying to figure out what is causing all these creeps to be attracted to her, and try to undo that.
The reality is that it isn't her fault that she gets that attention from those men. The fact that men stare at her and say things to her means that she really needs a guy to defend her. A good boyfriend should not get angry at her for this but instead stick up for her by telling the other guys off. It should not have any adverse affect on their relationship and shouldn't be a deal breaker.
It is important however that the girl makes sure that she shows those men that she is taken and doesn't flirt around with them. The boyfriend is probably going to have a fear of her leaving him for someone else because of the attention, this shouldn't surprise her too much. She just needs to build his confidence by letting him know he is the only one
Now to answer the question, personally, yes I would date a girl no matter whether or not she is a "creep magnet" and I would not be angry, irritated, of put off. It wouldn't change my feelings for her and it wouldn't stop me from having a serious relationship with her. Love shouldn't be changed by how other people see you and the person you love.
I definitely would. Even if she got lots of dates, or phone numbers off other guys, that gives me COMPETITION.
All I can say about competition is - bring it on! I play chess and a few other games, and when I lose at it, I learn what I did wrong and get better. I don't like losing.
Same with an attractive female - if she's spending time with another guy, I'll examine what makes him better than me. Perhaps the other guy is just more interesting, and more confident and happy than I am. So I'll need to work on myself.
It's a BIG challenge, and I like it. If she wants to talk to other guys while I'm present, she can. I'll just note my presence, then reciprocate by talking to new girls.
If she is attractive you need to be confident to deal with it and also have lots of money...girls don't like boys they like cars and money...she will stick around so long as their is money when that is gone she will leave...find someone else...because she can...