Doctor

Doctor appeared in the first book of the Dog Man series, as well as the 9th book of the Captain Underpants series, where he told Officer Knight and Greg the Dog the sad news after being extremely hurt from the explosion caused by Petey's bomb.

Appearances

 * Captain Underpants and the Terrifying Re-Turn of Tippy Tinkletrousers - The Adventures of Dog Man
 * Dog Man
 * Cat Kid Comic Club