Leopold is the loyal monstrous pet of Lord Felldrake Sheldgoose. In the wake of the warlock's defeat, Leopold was mummified and sealed in an Egyptian casket kept in Clinton Coot's cabana, being reawakened shortly after Felldrake's staff was discovered by Baron Von Sheldgoose.
Leopold is a chimera of parts from many different animals, with the Caballeros describing him as a "Monkey-Bat-Donkey-Rat", though April, May, and June identify him as possibly being a Chupacabra.
Though ferocious to his enemies, Leopold has a very gentle nature when interacting with his masters, hating to see them bicker and seeing them as parental figures. Felldrake in turn is very kind and doting to his beloved flying mount and sees him as the best way to travel.