From Introduction:
The trees that cover the Kingdom of Ermynia once grew on Earth, until they used magic to transported themselves across the invisible barrier and into the Land of Faerie. But the Ermynians themselves came later, when an order of fey knights pledged themselves to protect the kingdom and its grove. They built their castle here, and started new lives as a kind of martial monastic order.
These Ermynians resemble anthropomorphic mustelids, with rich, violet fur. They have long necks and skinny limbs, but their hands and feet are much larger in proportion than a human’s are. Their colour comes from the magic they use, which also colours the crystals that it flows through to get to them. These crystals, growing beneath the ground, are what brought the trees to Faerie in the first place. But albinistic Ermynians do exist. Those who cannot learn the ways of crystal magic are left without this purple hue darkening their fur. They do not become knights. Instead, they must find some other way to defend their kingdom.
While those who dwell in Ermynia sometimes have children of their own, who are born resembling their parents, they usually replenish their numbers by recruiting from the outside. The original Ermynians were faeries of the seelie courts, and that is still the main source of new prospects. But as the knights spend more and more time on Earth, across the veil between the worlds, they attract more attention from humans who wish to join their ranks. Those who are accepted must learn the ways of the trees, and change their forms to that of the other Ermynians, but their minds remain their own. Occasionally, outsiders stay in Ermynia without changing at all. Some are even considered valuable allies, but they always remain guests. Only those who change are truly subjects of the absent king.
When these knights go adventuring on Earth, they do not always have a specific quest in mind. Sometimes they seek out new sources of magic and wealth that might benefit their kingdom, but they also seek martial experiences, to increase their own prowess. Ermynians can be found serving as mercenaries in disparate lands, earning valour on the battlefield and solidifying their own reputations. Some have found only death upon this path, but others have become heroes of great renown. Some have used their glory to cement diplomatic bonds between themselves and the kingdoms of Earth. Their closest allies are the treants, but they have other allies as well.