This book was better than its predecessor. While I really liked Eon: Dragoneye Reborn, I enjoyed Eona so much more. The pacing was much more consistent, the characters were more compelling, and the story was much less predictable. I had a hard time putting this one down and I lost a fair amount of sleep while trying to finish it.
The romance in this book was well done. Eona and Kygo had amazing chemistry and I had no trouble believing their attraction to each other. I also loved the development of their relationship over the course of the novel. Eona's attraction to Lord Ido was unhealthy but never presented as anything else. I also enjoyed the relationship between Lady Dela and Ryko. It's great to see a non-traditional relationship (one between an eunuch and a woman trapped in a man's body) represented well.
The plot in this book was fast paced and action-packed. There was also a twist at the end that I didn't see coming, a stark contrast to Eon: Dragoneye Reborn, which suffered from plot predictability.
The biggest weakness of this novel, and the reason I removed half a star from the rating, is that I still found Eona to be an unlikable character. I was infuriated by her anger over not being trusted when a) she hadn't earned their trust after having deceived them for weeks (lies that caused great harm), and b) she continued to lie to them, giving them even more reason not to trust her. Eona also fails to trust the very same people who she's angry with for not trusting her even though many of them, such as Lady Dela, never gave her reason not to trust them. Her hypocrisy bothered me, especially because it was never addressed during the course of the story.
Despite my frustration with Eona, the fast moving plot, interesting setting, and likable side characters made this an enjoyable read. I'd recommend it to anyone who likes YA fantasy novels.