Oswald (ghost)

An ondageist is a sort of ghost with characteristics opposite to the better-known poltergeist. It is obsessively-compulsively neat to the point of annoyance, cleaning, picking up and putting things away even if you hoped, say, to finish that cup of tea. Oswald is one of these who haunts the home of Miss Level, Tiffany Aching's mentor in A Hat Full of Sky.