Purple pentapus

A Purple Pentapus is a small, five legged purple octopus that leaves small, red suction cup marks on the skin of the person to whom it is attached. It is tough to remove with brute force, but if one strokes its head, it will readily release its grip.

History
Purple pentapi were first encountered by Team Avatar in Omashu. They were first seen when Sokka climbed up a sewer pipe and came out with many of them on his face. They were later used by Sokka as a way to get Omashu's refugees out of the city. This was done by pretending that the marks left by the pentapi were actually a sign of a disease called Pentapox.

Anatomy
The purple pentapus is a five-eyed, five-tentacled, little octopus-like creature that lives in the sewers of Omashu. It is roughly the size of a human fist and though it latches onto targets, it is apparently harmless. Its tentacles have small suction cups that are used to grip onto the side of sewers in order to eat algae and other food.

Connection
The purple pentapus resembles an octopus, but on a much smaller scale. Unlike the octopus, the small invertebrate has only five arms, much like a starfish. Penta is the Greek numerical prefix for five. Pus is derived from the Greek pous, meaning leg, foot or paw. The name thus refers to the five arms of the animal, like an octopus is called after its eight tentacles.''