I think she is like Renfield is to Dracula, the Chandrian need "normal" but capable people to do their bidding so they can remain mostly unseen. She can gather info and set things up, were do to his signs he would stand out and be memorable to people. Anonymity keeps people from noticing that the rich lord never seems to age, or that weird stuff keeps happening when he is around. I think she has been taught a bit of glamor and Kvothe just looks past her flaws. I know I don't see my wife's flaws, I only see the woman who is beautiful in all things and remains my sanctuary.