She might still be a little sore, or she might just be going, "Something's supposed to be covering that spot!"

At least she's not like my Zelda and trying to even out the rest of her fur. Zelda was spayed over a year ago, and from where her tummy was shaved, all down the inside of her back legs she's still just got a light fuzz. And as near as anyone can figure, she's just trying to keep her fur evened out.