I'm a librarian who loves anime, manga, and reading a wide variety of genres.
This is probably the most complicated volume in the series. It follows three characters: Suzu, a Japanese girl who was transported to the Twelve Kingdoms 100 years ago and who became the servant of a sage (and therefore immortal); Shoukei, the daughter of a king whose father was overthrown; and Yoko, the new king of Kei.
Suzu has put Yoko, who she hasn't yet met, on a pedestal. She's convinced that Yoko, being another Japanese girl, would be her friend. Yoko's story is painful so far. Imagine being 16 years old, with "class president" as the full extent of your leadership experience, and suddenly becoming the leader of a kingdom where your ideas of common sense don't even necessarily apply. Shoukei is having a hard time of it herself, but she has so little empathy that it's hard to feel much sympathy for her. Her father had one fifth of his kingdom's population executed, and she doesn't understand why people hate her.
By the way, I checked, and chapter 16 of the hardcover edition of this book really does have 8 pages missing at the end. The chapter stops at a section break, so there's no indication that you've missed out on anything. I can't believe the paperback edition doesn't say "corrected edition" anywhere inside, because that's basically what it is.