I'll admit that it was a bit hard for me to get into this book. I was a bit lost since I didn't read the first book. My advice is for you to start with the first one. There are some series that are a bit more flexible when it comes to reading out of order although there is a potential for spoiling yourself for something. I'm sure there would have been less confusion for me if I had been able to read the first book in this series. It was a struggle for the first three chapters. By the time I got to the fourth it was a lot smoother for me.
I don't mean to be too nitpicky but I found the chapters a little strange. I don't make a habit of checking to see how many pages are in a chapter of what book I happen to be reading but they tend to be around the same length. Some books have short chapters while others have longer chapters. This book seems to have a mixture of the two unless that gets changed with the final product. That is possible. I also think I would have preferred the perspectives to be split up instead of bouncing back and forth during a chapter.
I admit that it was a challenge to keep reading this book. I do like the interesting take on Reapers but I always felt like I was missing something because I was since this is the second book. I've never read about Reapers that take on new appearances and are able to die. Also they don't seem to be immortal. The dark angel thing is different too since that would make you think bad even though all bad guys aren't not always so bad. Dark angels in this verse help save people. It would have been great if the book had a list of the characters so I could at least try to figure things out while I was reading or if it gave me some sort of summary of what happened in the previous book. TV shows do it so I think books should too especially when you're dealing with a series. I tend to read every book in the series so whenever a new one comes out I'm going to go back to book one and read through the latest one. Other people don't do that so it would be nice to have that little bit of a refresher before diving into the next book.