EDIT - Totally forgot to give Susan squirrel ears and a tail! That's embarassing. I will fix that at some point, but possibly not for a few days given other priorities and how tired I am, so... Yeah. Sorry about that.
Because she wants to see what all the patterns on her back are. That's the only reason she's asking. Anything else you might be assuming is wrong and you should be ashamed. ASHAMED!
Not wishing to speak for the comic while also knowing people will ask me about the technical details anyway, the "attract" effect on the actual players is relative to how they'd normally feel.
This is why Rhoda and Catalina have jaws in danger of hitting the floor and very strong blushes, and Susan just has a mild blush and is distracted enough to twirl her hair like that (which she will no doubt stop doing the instant she realizes she's doing it).