Naughty and nice list

The Thirteenth Doctor wondered if the list of children's names that Mr Henderson had in his office was the naughty or nice list. (COMIC: Holiday Special)

Frustrated with Santa Claus, the Twelfth Doctor told him to go and write a naughty list. Santa revealed that he had infact done so, and claimed that the Doctor was on it. He earlier recalled that Clara Oswald was marginal for the naughty list in 1993. (TV: Last Christmas)

Behind the scenes
The "naughty" and "nice" lists are a concept associated with Santa Claus, who is said to possess lists of children in the world who have been badly or well-behaved, respectively, with their placement being a factor as to whether or not they receive a Christmas present. The Thirteenth Doctor asks such a question because Mr Henderson is dressed as Santa.