4chan

They're not talking about sex workers or people with 'normal' sex lives and relationships. They're talking about the kind of person who's promiscuous, and gets called a whore or a slut because of it. The type of person who everyone assumes has a shitty life, or daddy issues, and hides behind sex.

Unsurprisingly, it's almost always women who get called the bad names, while the men who do it get called things like studs.