This series definitely improved as it went on. When they started, I kept reading them because they were easy, but I never cared about Jim, I liked each of the souls he was trying to save more. By the time i got to the end of the series, i began to like his character enough that I was disappointed that the series end. 
 I will say, as much as I enjoyed this book more than the others, the final resolution between Jim and Devina felt a little forced. I don't understand why, with 7 souls on the line it wasn't 7 books. That would have given the final resolution the focus it deserved.