Hiromi appears on the outside to be a mature, resilient girl, but on the inside she feels like she's falling apart. She is having troubles at home mainly because of her parents wanting to separate. Her dog, Junkers, tries to comfort her in ways no other dog can. You see, he can talk and grant her 3 wishes.

Haruka finds a cat in an abandoned building and names it "Nyan". Little does she know that this cat is actually "Ultra-Nyan" who has come from outer space. Using his mysterious powers, Ultra-Nyan helps Haruka and her friends foil the plans of a couple of no-good catnappers.

Ultra-Nyan's adventures continue. This time, he is tasked with finding the cause of the crows' sudden declaration of war upon the cats.