This will likely be a short review, since Christina Henry's Black City is short on plot and much more about the emotional development of Maddy and her relationship with Nathaniel. Oh yes, and day walking vampires courtesy of Maddy's deceased brother Azazel.
It's kind of silly, since most of the plot has to do with fighting the horde of vampires taking over Chicago, and yet they really don't play much into anything, since we're busy rescuing JB from Titania, watching Maddy grow intimate with Nathaniel, whom she has a love/hate relationship with, and all kinds of conversations about how Maddy is slowly allowing Lucifer to make her his hound.
Honestly, it's a quick read, and it develops the characters a bit more, but other than explaining the relationships between Puck and Lucifer and adding a few other major players to the mix, it's fluff waiting for another book to happen. Also, there's so much angst (and a cliffhanger ending) that I felt Ms. Henry should include a copy of "Nadia's Theme" in each copy as a soundtrack.