Is the spine hanging out of his mouth like his tongue, or is it kind of like a piece of food hanging out of a person's mouth?
It's a tongue made out of someone's spine. Incidentally, that is based on the little yellow thing dangling out of the famous picture blobfish's mouth... which on second look probably wasn't its tongue.
Happy Halloween! Finishing things off with a Trick-or-Treater: And as a bonus, a puking pumpkin I made (first time carving one):
Hah! I made a puking pumpkin this year as well. Nonetheless you made this Halloween on TFW a great one. Guess we'll have to wait another year...