It looks like someone wanted to make a cosplay, but something isn't right. Doofenshmirtz turns himself into a platypus to defeat Perry in the episode named Doofapus. As he had said, the best way to defeat a platypus is to become a platypus. So we have this mix of a teal animal and his enemy Heinz Doofenshmirtz. Phineas and Ferb Dr. Doofenshmirtz Platypus Sticker, in case, if something went wrong.