I really wanted to enjoy this sequel but it was just mostly a repetition of the first book. I started rolling my eyes when it felt like the 20th time that the characters thought "oh no I feel something - MUST SHOVE IT OUT OF MY MIND!". It's ok, we get it, they're anxious and torn, like emo teenagers, but come on. How are they supposed to be mighty gods when they're most afraid of even *thinking* about things? It also makes a really boring book, since we already covered all the angst in the first one. So you like each other and it's scary, OK, what happens next? But no, that's the extent of their though process. Boring.
This book could have been a novella, because honestly the character development was nearly non-existent. Hades goes through turmoil but learns _nothing_ by the end of the book. Also, he's so emotionally abusive that it was painful to read how blind Seraphia was and how easily she gave in. Again, like in the first book, the whole romance relied almost entirely on some magical sexual tension, not actual growth. I still am mostly interested in Lucifer and apothecary.
The only thing I really liked (and why I'm rating this 2* instead of one) was the world building, still! Exploring the Underworld and the different tasks made me feel like we were part of an adventure. The Greek mythology was fascinating, but I wished for more of it. I still don't really understand how all the gods work together (why is there a Lucifer? Who is not Satan apparently? Confusion.), but I still enjoyed all the creatures and scenery.
I think I gave up trying to like the book when Seraphia's fairy friend mysteriously managed to make a potion to counteract hell's number one and only rule. Hades is supposed to be an all-powerful ruler of the underworld, and even he doesn't know any way to bend the rules, but somehow a random fairy from the human world is like "yes I have a lab, I can trick the literal Hell". It's just one example of the lazy writing in this book.
Speaking of the fairy friend, I think the author should have spent some time developing the friendships too. In book one, we're supposed to believe Seraphia is not exactly in her feelings, but she's almost nothing but feelings (it actually seems that she actively chooses to rebuke logic and rationality). We're also told that she doesn't have close friends and that she's closed off, and the only person she loved, her nana, is dead. So uhm ... Why does she want to go back to earth so badly? Why is she all of a sudden so concerned with her friends all the time? We see almost no scenes with anyone but Beatrix, and even their friendship seems to be lopsided, as Beatrix's only function is to help Seraphia. I just found it hard to root for her, because she wasn't developed at all. We just had to have things at face value, we didn't actually get to see her development (like nurturing friendships).
Also, I hate to be this person, but the plot twist at the end was completely predictable.
I'm going to read the last book, because I want to know how it all turns out, but I don't think I will even remember the plot to this trilogy in a few months' time.