Polly is both an annoyance and disgrace to Hatusne Mikaiju, and has been that way ever since he was altered by a rogue scientist to feel no fear whatsoever. He approaches danger nonchalantly and treats threats as challenges. Now, he particularly enjoys frustrating Hatusne any chance he gets (which luckily is very rare).
He's very short, and beneath his head is covered in four brown polygons that are supposed to be a trenchcoat. A large pirate's hat of the same color and bearing the image of a paper airplane covers the top of his head so that it's shaded black and only shows a pair cartoonishly bright and large eyes. His beak sticks out from under the hat, yet is still black.