This story continues (precedes? I'm unclear enough on the Marquis' physiology to know where this would fall in the timeline) Gaiman's Neverwhere, giving us further insight into this cold-blooded villain and his coat. The coat is important because of its pockets, but I'll let you figure out why. I was glad that I had revisited Neverwhere last year in audio format, since without it I might have been a little lost as to some of the details. The story was a well-told tale, with the usual Gaiman mysticism and craft, so if you're a fan, you should check it out.