Dermatophagia (sufferers can be called wolf-biters) is a form of obsessive-compulsive disorder wherein a sufferer compulsively bites their own skin. Sufferers typically bite the skin around the nails, leading to bleeding and discoloration over time.
Dermatophagia sufferers chew their skin out of compulsion, and can do so on a variety of places on their body. Sufferers typically chew the skin surrounding their fingernails and joints. If the behavior is left unchecked for an extended period, callouses may start to develop where most of the biting is done.
Skin chewing can be bolstered by times of apprehension and other unpleasant events. Blisters in particular can cause a feeling of desire to pull or bite off the affected skin (since the skin is dead, thus easily pulled off), which could be detrimental, causing infection. Another disorder, known as dermatillomania, the act of picking at one's skin, can sometimes accompany dermatophagia.