Mage is a drifter, a freelance photographer who who gets more than he bargained for when he helps out a distressed woman at a bus station in a remote Canadian town. She gives him a key, and suddenly he finds himself on the run from strange people, aided by stranger people, and in the possession of the strangest powers. He has to learn how to use those powers before he gets caught, and killed, by the people who want the key back.
This is a fun fantasy chase, with good characters who have semi-believable reactions to the sudden possession of Powers, and some great little details. It is differentiated from the mass of urban fantasies by using settings from Japanese mythology (whence the title), and by being agreeably un-padded.