Riot likes to lick anything metal too, keys, cabinet handles, earrings, buttons on your pants if he's on your lap etc. The vet said it's not too much of an issue just to discourage the things like biting on the cabinet handles because it can wear down his adult teeth very fast.
As far as the black bump goes, I'd call the vet, especially since it hurts to touch it.
__________________ Proud Mamma to Riot  and baby Chaos  |