"Servant of the Bones" is a 1996 novel by Anne Rice, detailing the existence of a spirit or ghost. Although it deals with the supernatural, it would probably not be categorized as horror, but more as an urban fantasy. Like Anne Rice's earlier, and most well-known work, Interview with the Vampire, the book consists of a framing story where a mortal records the biography of a supernatural entity.
The protagonist of the story is Azriel, who was a member of the Jewish community in ancient Babylon at the time of the conquest of King Cyrus. In a magical ritual gone wrong, he is killed and his spirit is tied to earth as an immortal, and powerful spirit. Over the centuries, he serves different masters, only to be awoken in modern times in order to stop a cult leader with an evil master plan. Being an immortal spirit with super strength, speed and endurance, this does not produce much of a challenge for Azriel, and the book concludes somewhat anti-climatically.
This book is very much an Anne Rice book, and a reader who likes Anne Rice will probably like this book, while a reader who doesn't...will probably not. This is also specifically one of the books that Anne Rice wrote after she decided she didn't need an editor, and I think it suffers for it. This book has several things going for it: Rice's lush, evocative description of the world ancient and modern, a conversational tone that is easy to get into, and the slow unfurling of supernatural mysteries. What it doesn't have is much dramatic structure. Rice just wants to describe people, places and events, and these are often written without much explanation of what role they play. The central protagonist of the story, being dead and invincible, doesn't have much room for character development. So what we have is a record, a history, as much as a novel. Some interactions seem to exist just so Rice can throw a scene in: for example, where a woman who is dying of cancer and grieving her assassinated daughter decides that what she really wants to do is have sex with our unearthly handsome ghost protagonist three times. Does this make sense? Not really. Does it make a good scene? Yes, especially since there has to be a sex scene in an Anne Rice book.
Given time, I will read pretty much anything Anne Rice has written, and I liked many things about this book. However, I do feel it would have been a better book if Rice had tightened up her narrative instead of just revelling in description.