In the words of the great Mark Latham: "Fuckin' idiot"
I don't think it has anything to do with being a "slut" or a "whore" at all. You will always find certain men or women who will just take the opportunity even though it's ethically, morally and legally wrong to do so. I've heard of many cases where women have raped men and abused their position of power - two cases: 1. In certain secret police organisations in Eastern Europe when they were under Communist reign, females from these organisations would rape and torture inmates. 2. Cases where female doctors/dentists/anaesthetists have abused their patients when they're knocked out.
Rape is a problem which affects males and females from both sides, however, it is true that the amount of females being raped by males far out weights the amount of females raping men.
The point I'm illustrating is that rape is not a sexual act, it is not a sex thing, it is not the want to impregnate but it is a matter of POWER. Even with the anecdotal evidence provided in the Bulldogs case, that woman did have sex with them the night before (in your definition a "slut" or "whore") and yet, it didn't stop them coming back the next night, after she had refused sex and raping her. Notice that there were multiple football players involved and their size compared to the woman. They had the power and they abused it.
I think personally, that labelling women who have sex as "sluts" and "whores" is really misleading (and I don't know, used by men to transfer their guilty conscience?) because men do exactly the same thing and often have tonnes more sex with multiple partners.