Perhaps the words stem from the notion (for some) that ladies who enjoy truly enjoy sex, in all its variations, are somewhat deviant/dirty/nauty. It's the madanna/whore syndrome. Hence the use of these words at websites gives the impression that something other-than-the-ordinary is contained within.

I woudn't go so far and say that men who refer to women in these terms suffer from a lack of self-esteem. In most cultures, men are simply taught that women who enjoy sex and perhaps have their more than their fair share of partners are sluts and asking to be used. Note that, for men, the contraverse isn't true.

It also depends on context. Some people enjoy using such terms as part of their sex play and derive great pleasure from it...Just my 2 cents.

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Nubian