Throughout this series, Thorn often lusts after men because they are seraphs or the progeny of seraphs. I understand that she can't help it and I think the idea is intriguing. However, all this lust never culminates or amounts to anything. Books don't require sex in order to be good but if Thorn is repeatedly throwing herself at guys, I come to expect something to result from it. I expect her to find a guy (human, mage, kylen, seraph, WHATEVER) and pick him AND end up with him. When I finished the epilogue, I felt incredibly disgusted but not at all surprised. It seems like all three books so far have ended somewhat abruptly with loose ends, just a few pages after the battles are over.
That being said, the characters are well-developed and likable, my favorites being Audric and Eli. And, of course, my favorite aspect of the books is the world-building; I'm a huge fan of seraphs vs fallen/spawn in a post-apocalyptic setting.
The end leaves a lot unsaid and afterwards I went to Ms. Hunter's website, hoping for news of a fourth book though I had a sinking feeling that I wouldn't find anything. One page on the site calls the series a trilogy but I would still love to see what happens to Ciana, Thorn, Cheran, Rose, Audric, and the seraphs. Hopefully there's some evil left for them to fight.