Krampus

Krampus The Wicked, The Germanic Pantheon god of Wickedness.
First appeared in Season 2.
Krampus was first seen accompanied by Krampette on Christmas 1985.
He punishes the wicked at Christmas time, Fionn quickly made a truce with Krampus and Krampette and even invited them to terrorize Blaine Lennon.
When they came to the big party at Corvin Farm before The War In Tartarus, Fionn invited them to terrorize Blaine every weekend for the next three months, which they gladly accepted.