Don't take it so seriously, that's just young men doing their thing. I know it's a PITA, but the ones you should look out for are the ones that are persistent after you told them to buzz off. As far as the whole *rape* thing goes, that's not too common fortunately.
If you want to know why guys hit on women so much,
You want to know why men (Actually, *EVERY* male of *EVERY* species that reproduces sexually, other than a relatively few biologically defective individuals - no, this isn't gay-bashing, though it may sound like it - see the footnote I'll add at the bottom so as not to derail the thought I'm actually going for here) hit on women (or their species' equivalent) almost constantly? I can tell you *EXACTLY* why, but chances are, you'll do what everybody else seems to: Figure out some way to delude themselves by saying "No, that can't possibly be right! We're better than that!" But that response, regardless of the words it gets expressed in, is pure, complete, total, utter *BULLSHIT*.
But here ya go anyway:
EVERY SINGLE LIVING THING on planet earth that uses sex as a reproductive method is two things, regardless of what species it belongs to, or *ANY* other consideration you can come up with. (This includes many, although not all, plants, bacteria, and fungi)
The first thing it is, is the result of a genetic combination that, somewhere back in the depths of pre-history, figured out the trick of making copies of itself. There are no exceptions. This statement applies to *EVERYTHING ALIVE THAT YOU CAN NAME* (as well as some things, such as viruses and prions, that we can't really say "This is/isn't alive" about with any more certainty than a reasonably educated guess) with absolutely no exceptions for any consideration you can dream up. None. Period. No discussion possible. Try to deny it using any logic you like, but no matter how well you argue the case, you will still be wrong. It's honestly that simple.
The second thing it is, is the offspring of a long line of living things that have (wait for it...) SUCCESSFULLY CREATED OFFSPRING. Now I know how simple-minded that sounds - I forget the word generally used for such statements - Tautology, perhaps? - but it remains true, regardless. NOTHING ALIVE TODAY has in it's genes any trace of EVEN A SINGLE ANCESTOR WHO FAILED TO REPRODUCE. By definition, if something is alive, it's the culmination of a line of successful reproducers that stretches *ALL THE WAY BACK* to the first cell that learned how to combine its genes with those of another similar cell to create a new copy (with relatively minor differences) of itself.
One characteristic shared by every such living entity, male or female, is the instinctive urge to make a copy of itself this way - even though sexual reproduction is, when considered in the close view, "only half a copy". How, precisely, does a male, of any species make a copy of itself? That's right - By getting his sperm (or his species' equivalent) into contact with the egg (or equivalent) of a female of his (or a closely-enough related to be interfertile) species.
Therefore, it's quite clear that, biologically speaking, the best strategy for reproducing his genes for *ANY* male, is to get as much of his sperm as he can into close proximity with as many viable (which usually implies "of his own species", give or take combinations such as "horse+donkey=mule", etc) eggs as he can. In other words, by mating with as many females of his species as he can.
How does he do that? Well, it's a pretty sure bet that if he makes no attempt at mating, he's going to fail to reproduce, wouldn't you say? "Outta the gene pool, buddy. You're done!"
The most successful reproducers get that way by mating with as many fertile female partners as possible, by any means that works - including (perhaps even "especially", in some species) flat-out "I'm gonna fuck you and blow my load inside you whether you like it or not" rape.
For a male, the best strategy is to mate with as many females as he possibly can, as often as he's able, no matter what it takes. In this way, he (hopefully) assures that his genes will go on. For a male, this strategy is biologically "cheap" - it takes little effort for a male to manufacture gazillions of viable sperm cells and spread them as widely as he can. For a female, where the majority of the effort of reproduction is heaviest, the best strategy is to only allow the "best" (You decide what constitutes "best" in any given case - I don't care enough to even try) male to mate with her so that her own genes (which, just like the male, she instinctively wants to pass along) have the best chance of surviving to the point where they can, in turn, pass their genes, and thus, at least some portion of the female's own genes, along to the next generation.
And that, nothing more, nothing less, is the reason males are always trying to mate with anything that will hold still long enough to get their dick into it, while females tend towards being "picky" about who/what they allow to mate with them.
The footnote I promised:
No, it isn't gay-bashing, and here's why: What I said up there is just as applicable to zoos/beasties (including myself), or fetishists that get off on fucking the tailpipes of cars, gays (or whatever the politically correct alphabet soup stupidity they insist on being called happens to be this week), screwballs who think that fucking corpses is great, or any other form of sexual gratification that doesn't result in the male's sperm at least having the realistic chance to meet up with a genetically-compatible egg. From a purely biological view, anything but "male squirts sperm into same-species female" is a maladaptive aberration - a clear, inarguable demonstration that the life-form doing it isn't fit to pass its genes on to the next generation. In terms of biology, defective.