He was only seen in the episode "Transparents!" and the video game The Fairly OddParents: Enter the Cleft!. Francis brings him to show and tell for school, where he shows off a jar full of first-graders that he feeds to his dog to keep his coat shiny. Mange ends up biting Mr. Crocker in the leg, earning Francis a "D for Dog". Mange reappears at the end of the episode, after Cosmo and Wanda poof him into a box in place of a captured baby dinosaur originally wished up by Timmy Turner, foiling Mr. Crocker's plan to expose Timmy's fairies, and causing Mange to bite Crocker yet again.
In a later episode titled "You Doo", Francis's only pets are cats.