July 18, 2013
Tonan no Tsubasa (39)
When Shushou says, "But those aren't real towns. They don't have a riboku," she is commenting on the etymology of riboku (里木), which means "a village with a tree."
The term "koushu no tami" (黄朱の民) is explained at the end of chapter 15.
In chapter 44 of A Thousand Leagues of Wind, Enho tells Youko that emperors can't have children. (He also explains the 100 percent inheritance tax, though people like Shushou's father have figured out a big loophole.) And yet Gankyuu says the Imperial riboku can bear the emperor's child.
Googling around, I found a couple of Japanese message boards where the same question was raised, though nobody could offer a satisfactory explanation other than editorial error. Or Gankyuu is simply misinformed.