Heres Jack with a sack full of Santa's Elves. (its a prank)
He's a neutral party. He's not evil, he just hates Santa for not giving gifts to his favorite children (a.k.a: the 'trickers' on Halloween)

-He's The Halloween holiday (of course).
-He's a walking corpse. (died at 16)
-He's a thief.
-He knows magic and witchcraft. He can cast spells and curses.
-He has cat ears because his girlfriend used a cat-soul in exchange for bringing Jacks soul back
-He has no neck since he died from being beheaded. (he almost always wears a yellow scarf)
-He's mischevous. Using any and every oportunity to play a trick on someone *mainly Santa*

-BIO: He was a petty theif who always loved to play tricks on people. One day, on October 31, he played a trick on the queen, who didn't take pumpkin pie in her face quite well, and the Queen had him beheaded.
He was resurrected by his girlfriend *who was a witch*. She used a cat soul in exchange for bringing his back (hence, the kitty ears) And when he was, he murdered the queen and all her subjects on October 31st to get his revenge.

But lately he's grown to like sweets, he dropped his murderous ways to steal candy, and give candy to others who liked it *mainly children*
But he resents those candy holding misers who don't give any. Every once and a while he'll commit a murder or two...
******
Hope you like the bio