The idea of feeding off emotions doesn't make much sense to Hermione, but she chalks it up as yet something else she'll have to research at a later date and lets it slide for now.

"Would it have made a difference if mages had been asked to stay behind on this mission? I'm assuming not, of course, as we had no way of knowing that we wouldn't just be fighting demons but would end up right here in their domain." Shivering a little, she looks around, careful not to glance at any of the markers herself. "All things considered, though, I can understand why they'd make any attempt possible to leave here."