In “The Krampus,” an old circle of friends seeks to banish holiday stress as they gather at a Brooklyn bar to drink and commiserate. They sing songs, crack jokes and tell stories that are by turns heartfelt and heartbreaking, while others are simply filthy. The lighthearted banter soon takes on a more personal tone, as the group reflect on their own childhoods and memories of the Krampus story. The Krampus’ is a play about families of chance, families of choice, childhood monsters, and the joy of new traditions.