At least some content in this article is derived from information featured in Harry Potter: Hogwarts Mystery. Spoilers will be present within the article.
Duncan Ashe was a wizard who attended Hogwarts School of Witchcraft and Wizardry in the second half of the 20th century and was sorted into Slytherin. He was friends with Jacob from his first day at school until his dying day. The two were noted to be mischief makers by others, and frequently visited Zonko's Joke Shop. At some point, he and Jacob also broke their brooms. He was also friends with the school poltergeist, Peeves. After his death, Duncan returned as a ghost and stayed at Hogwarts, though he rarely showed himself to the other residents of the Castle.
- Harry Potter: Hogwarts Mystery (Appears as a ghost or a spirit)