Yeah I'm confused here. There's lots of dialogue that, depending on who is speaking it and how, changes quite a bit about the story being told here. Is the lady saying that we have to make him understand that they aren't people, or is it the disguised vampire? Does the lady know that the big ol' vampire baddie is in the room making the poor thrall do things he doesn't want to, or is she going off of previous knowledge and saying "the vampire that created this creature takes over consciousnesses, and only sees other beings as tools?" There's a whoooole lot of implications that aren't clear. It's possible they're not meant to be, but it's still a confusin' chapter because I can't tell who's saying what in a few places and I'm unsure exactly what one statement is informed by.