Rufus is a naked mole rat, the pet friend and soul brother of Ron Stoppable, and the tritagonist of the Kim Possible franchise.
Rufus lives almost full-time in Ron's pants pocket and accompanies him everywhere. For an animal, he is exceptionally intelligent, but average by human standards, and is capable of vocalizations approximating limited speech. It is unclear if his "speech" is actual or a case of "audience filter" and not understandable to anyone other than Ron himself.