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)

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-behaved 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.