They prefer the taste of there own nails to other peoples?
Maybe it's like stress eating. No food at hand, so replace by nails on hand.
It's a habit usually caused by nervousness, but no one chews off ALL of the nail.
Stress I believe, but I've never understood it. Eeewww.
It's delicious. Topped off with a lil hair? FORGET ABOUT IT!
Love the new avi!