Well, now that MASIAH's morally-dubious statement has been cleared up, I see no reason not to.
I have this terrible habit of picking my fingers until they bleed.
I'm a compulsive nail-biter. My nails have receded so far back past my fingertips that I now resort to chewing off the skin
around them. It's disgusting and will undoubtably someday lead to infection, but it's a hard habit to break.