
This is the second book in the series, but concludes the 1st "episode", which is Youko's story. At the end of the last book, we left off on Youko meeting a mysteriously large rat creature while on the verge of death. We finally learn more about this person, whose name is actually Rakushun and is a half-rat half-person (called a Hanjyuu in this world).
Meeting Rakushun becomes a huge turning point for Youko. She is unable to trust anyone in this world, but Rakushun becomes the first person to earnestly lend her aid without any malicious ulterior motives. Through him, we learn more about the world (literally, he's full of infodumps) while they travel together to Youko's next stop in the adventure.
Youko's character development is accelerated by meeting Rakushun, as he serves as a counterpoint to all her preconceived notions about this world. Of course, Youko continues to fend for herself when she has to, which is nice to see.
There's not much more that I can say about this book without spoiling the rest of the plot, so spoilers below!
Spoilers
I honestly thought that the anime did this part of the journey to En much better than the book, simply because they spent more time fleshing out the world not through infodumps, but real interactions between Youko and the citizens of Kou and En. She spends much longer in Agan trying to catch the boat, and she develops some life skills as well.
That said, I'm happy to report that the En-Ou and Enki are just as delightful in the books as they are in the anime.
It's unfortunate that much of the interesting "climax" gets cut out here, as we don't see Youko take the throne back from Jyoei. She saves Keiki, and the rest is basically hand-waived away. I guess Ono-sensei isn't too interested in showing how all that went down, since Youko's choice to become King of Kei is done by that point.
The next book isn't about Youko, but rather about Taiki and the country of Tai. This series is pretty famous for jumping around, but at least the next episode is a complete story in one volume. I've already got Book 3 in hand, but we'll see when I get around to reading it haha.

