As with Havemercy, this book follows four paired protagonists, Kouje and Mamoru and Caius and Alcibiades. Unfortunately, the Caius and Alcibiades chapters felt like filler half the time. They were often amusing and replete with bantery dialogue, but filler nonetheless.
An additional annoyance was how the Xi'an characters constantly referred to themselves/their country as "Ke-Han." Way to privilege the perspective of (white) Volstov and to other (Asian) Xi'an.
The book's saving grace for me was Kouje's and Mamoru's plotline, which is just the sort of quest narrative that I most enjoy. And, as I mentioned above, there's no lack of wit and humor. While that combo was sufficient for a fairly pleasurable reading experience, however, it wasn't enough to make the book actually good.