Dorothy (The Wonderful Doctor of Oz)

Dorothy was an American teenager who served as a temporary companion of the Thirteenth Doctor.

She originally identified as a male called Theodore. (PROSE: The Wonderful Doctor of Oz)

Behind the scenes
Dorothy is named after Dorothy Gale, one of the recurring protagonists of L. Frank Baum's Oz books. Notably, the real name of the Seventh Doctor's companion Ace was also a reference to the character, with some details of her life story echoing that of Baum's Dorothy (such as having been propelled from her ordinary life into another world by a "tornado").

Although she is never explicitly confirmed as such in the narrative, Dorothy is very clearly intended to be interpreted as a transgender individual.

Dorothy holds the honour of being the first trans character in the DWU to discover their identity in "real time" through the course of the story in which they appear, as opposed to already having their identity established as part of their backstory. As a result, Dorothy is referred to throughout the majority of the story by her birth name and with masculine pronouns, before switching to her true identifications upon transitioning.