"'But I am not fishing; don't compliment me.' Have no fear of that!" Hah!
This will probably sound strange, but I think it's sad that Frankie thinks so little of Fanny ("I do not understand how she can truly value such a mouse as I appear to be, even if she is no longer controlled by a demon."). I mean, it's natural that she chafes at having to pretend to be someone she's not, someone so very different from her, but still...to disbelieve that someone could value her? That is very harsh. Here and in general, I think Frankie extends less grace and understanding to people around her than Fanny.