Good ole Krampus. Some of you might have heard of him, but probably don't know too much about the (terrifying) details.
Well, for starters he's half goat and half demon. Odd, but okay. He rolls into town on December 5th with the main aim of his visit being to literally beat "wicked" children with birch sticks into being nice. The next morning, December 6th just so happens to be St. Nick Day and in traditional German culture, children check their shoes to see whether they got presents for being nice or a rod for being naughty.
So, basically, he is Santa's BFF because he keeps children in line just in time for Christmas. Nothing like a little Christmas demon, eh?