Platypus

"They don't do much, you know."

- Charlene Doofenshmirtz on platypuses.

A platypus is a semi-aquatic, egg-laying mammal, native to Australia but known to be domesticated in America.

Description
Platypuses have turquoise-colored fur, along with a beaver tail and a duckbill. Platypuses are generally "mindless" and very dull, tending to never "do anything." Platypuses do, however, have the ability to be intelligent, as evident by Agent P, a highly prestige member of The O.W.C.A. Platypuses, when stressed, express it by sweating milk. (Phineas and Ferb, Perry the Platypus (song), "Does This Duckbill Make Me Look Fat?")

Platypuses naturally make an odd chirping noise that appears to be understandable for another animal or animals. Humans, however, appear to have no understanding of the chirp whatsoever. ("Perry Lays an Egg," "It's About Time!", "Interview with a Platypus")