They relate to her. She says stuff that many women think, but won’t say out loud because it’s taboo/inappropriate. Like an outlet for their more degenerate side. It also helps that her attempts at being sexy, often end up with her being the bottom of the joke. It’s nice to see someone who can laugh at their own flaws instead of getting defensive, and again, that whole “trying-to-be-seductive-but-you-just-end-up-looking-like-a-fool” thing is relatable.
Also she’s extremely charismatic, which not only makes her entertaining to listen to, but also adds to the feeling that you could easily get along with her, even if you yourself aren’t particularly outgoing .
