Ankou was a cat-like creature in the service of Mischievous Rain. Although often similar to a typical cat in size and mannerisms, Ankou possessed a distinctive third eye in the center of his forehead. Later revelations about the creature would cause Croaker to surmise that, like Mischievous Rain's children Baku and Shin, Ankou must have been a kind of demon whom Mischievous Rain had bound. Ankou could travel through shadows. During the subjugation of the Ghost Country, he was apparently fearsome enough to coerce or persuade several revenants, powerful monsters in their own right, to serve the Lady's Empire. He also transformed into a very large beast described as larger than a tiger.