[Natori is pretty used to getting strong reactions from ayakashi once they realize he's an exorcist. Often they can tell just from his scent, or they figure it out once they realize he can see them. Their response is usually some combination of running away, cursing his wretched existence, or immediately trying to eat him, so in comparison, Broca's reaction is pretty subtle. Natori clocks it anyway, but facing exasperated sighs for revealing his occupation is just part and parcel of the job. Exorcists suck. No one wants to spend time around them. Natori knows he's not an exception.

So he just assumes Broca's got the common sense (if very ayakashi-coded) distaste for exorcists in general, rather than experience with one in particular.] 

Well, I don't know if I'd claim to be an "expert." [The unstated "but": he still thinks he's right and nothing will change that. But then again, it also doesn't matter if the other people here believe him for now, so long as it doesn't get in the way of whatever they need to do to get out.] I can say this is the first time I've seen something affecting this many people. Is everyone in this place from another world, or whatever we're going to call it?