In "Hogfather" the Auditors employ Mr Teatime, an assassin who attempts to destroy the Hogfather using teeth found at the Tooth Fairy's castle to control children. Death cannot enter the Tooth Fairy's castle because it is constructed from the imaginations of children, who have no concept of death, and therefore arranges for Susan to foil their plan instead. After removing all of the Auditors' human agents from the Tooth Fairy's country, Susan saves the Hogfather from being destroyed by a group of Auditors who have taken the forms of dogs. She later kills Mr Teatime by impaling him with the poker she uses to threaten monsters.