In some European countries Santa Claus doesn't have to do all the work by himself. Santa's only job is rewarding nice children. The naughty children get a visit from something far more hideous, the Krampus.
The Krampus is depicted as a horned, shaggy, bestial, and demonic creature. In many depictions the Krampus looks like popular images of the Devil, complete with red skin, cloven hooves, and short horns.
When the Krampus visits your house you don't get any presents. The Krampus comes with switches and is a tormentor of naughty children. He may simply leave a lump of coal as a warning for them to shape up, or if the children have been especially wicked, the Krampus may tie them up with chains and whip them with switches.
Because of the Krampus Christmas Eve became known as the time when children were best behaved.