I don't think that the dog was possessed. He was just angry because of the tick and fleas that caused itchiness in his paws.
Is there a human version of this? Like people cutting themselves or picking their own skin till it bleeds?
Trichotillomania [video=youtube;eRvk5UQY1Js]https://www.youtube.com/watch?feature=player_embedded&v=eRvk5UQY1Js[/video]