is the Dog Star, infamous for his fiery temper. The main character of Dogsbody
, he is sent to Earth in the form of a dog as punishment for a crime he claimed he didn't commit. On Earth, he must find a certain object during his life as a dog if he wants to return to the stars.
He is adopted by girl named Kathleen, who names him Leo. He is also referred to, by other characters, as "Shamus", "Shamus O'Cat", "Shamus Rat", "Rat", "Dog", and "That Creature" - and Miss Smith, without any prompting at all, calls him Sirius.