I've been reading this series since book 1 came out and it's one of my favs, one of the few that I read immediately upon release. It has paranormal romance and historical fiction mixed in with a dash of steampunk, three of my favorite genres. Callihan as usual has intermingled these genres in yet another wonderful tale. While we've met Sin before, Layla is a new and unique creature called a "Damnation". As she knows nothing of this paranormal London, she is surprisingly adaptable to what's going on in her life. I loved the romance between Sin and Layla, but felt a sense of sadness as this series comes to an end. I loved the brief interactions with many of the couples we've met in the past and am really going to miss this wonderful world. Make sure you read this series in order so that you get the whole picture. I almost wish I hadn't read them all so I'd have this whole series to binge read.