Gytrash.

Emma had heard of these creatures briefly while at Durmstrang. One thing she remembered about them was that they were sort of like the ghosts of animals, dogs in particular. They were possibly the spirits of crups, which contained a similar forked tail if she recalled correctly. So why did light affect them, but not fire. That was an interesting question indeed.

Thinking back to her studies Emma tried to come up with a good answer. "Professor, does it have to do with the form of the Gytrash. Aren't they believed to be the ghosts of animals, possibly crups because they share the forked tail?" Emma questioned. "Because they are a ghost form, fire would not affect them the same as light. As some people have mentioned, fire can be blown out, while light stands strong and doesn't waver." Emma had no idea if what she said was right, she would have to wait and see.