Yeah, this comes under my 'destructive grooming' set of stimms.
I used to bite my nails down until they all bled, I managed to grow them long up until the previous few years of unemployment when I've been biting again - not as bad, but it's still there. Even with long nails I still bit around the cuticles and by the side of the nails, it was a case of trying to neaten them up by biting off the bits that were scruffy...from having been bitten to begin with. You bite your nails, then there's a rough bit so you have to bite to get rid of the ruff bit, before you know it the whole nail is bitten down...and of course you can't keep the others long if that one is short. ARG!
Nasty tasting nail polish never worked for me, clear nail polish in general did though - it meant if I did bite it'd not just be messing up my nails but also the nail polish too, so I was less likely to bite as it'd cause twice the damage...clear is more attractive on short nails.
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Bloodheart
Good-looking girls break hearts, and goodhearted girls mend them.