In Eastern European folklore what demonic character rides along with Saint Nicholas?

In Eastern European folklore, the demonic character that accompanies Saint Nicholas is often known as Krampus. Traditionally depicted as a horned, goat-like creature, Krampus serves as a counterpart to Saint Nicholas, punishing naughty children while the saint rewards the good ones. This duality emphasizes the themes of reward and punishment during the Christmas season. The legend of Krampus is particularly prevalent in countries such as Austria, Germany, and Hungary.