The Twelve Kingdoms (2002) IMDb
On an ordinary day in modern Japan, a white-haired stranger in archaic clothing appears before a maladjusted schoolgirl and swears allegiance to her. In trying to save her from magical beasts that suddenly track her down, he brings her and—by accident—two other teenagers to a secondary world.
That world is square, divided into twelve kingdoms of equal size. Absolute rulers are chosen by “the heavens” through shapeshifting pacifist proxies, and can live forever. Without a good ruler, a kingdom falls prey to natural disasters. Pregnancy does not exist. All new individuals grow on special trees, and so on.
There is a huge ruleset and terminology describing the world, a uchronian East Asian mythscape vaguely patterned after Legalism and other ancient Chinese philosophies. Indeed, even to several of its inhabitants, the way the world is arranged seems so absurd that the villain of a major story arc commits every “sin” he can think of just to see whether or not “the heavens” care. Some of the series’s last lines indicate that the primary heroine herself isn’t certain.
Serious fantasy adventure in a world of absurdly obvious artifice. It isn’t simply a crypto-Chinese utopia (with furries). It is made perfectly clear that humans would abuse and corrupt even such a structured world (with furries), and one major sympathetic character resents the very presence of rulers. That’s nice, but even so, the plot follows only those blessed by high birth or other privileges. Consequently, the hierarchical system is viewed almost entirely from the top, and romanticized in spite of talk about suffering populations as a consequence of rulers being too important. The visuals and much of the music are excellent. Character design and development are good, and there is appropriately no fan service.