Unique and Well Written
Most times the authors of these types of novels can't stretch their imagination far enough to create a genuinely unique fantasy.
This author had no such difficulty. The people, dialogue, plot, setting, all were done in such a way that I could envision being somewhere other than Earth. When the connection to the title was revealed, I was already so invested in the characters that I just smiled and thought, "Yep, that's apropos".
There was a lot to this story so I wouldn't recommend reading it too quickly. Take time to digest what's happening, even with the action scenes, because it'll make it all the more enjoyable.
There were times, however, when I was confused by some of the names given, and if not for the capitalization and context, I would have been further confused. And there were other times a word was capitalized as if a name, but didn't fit the context for that. For example, "Younger" "Infernal" "Summer" [I know this wasn't supposed to be a name in context] "Gap", etc. This happened quite a few times which did trip up my reading on occasion, and that's why the four stars.