Lords and Ladies of the Faerie Host

The Sidhe are the First Born of the Goddess Danu, and as such are closer to her in power and glory. They govern the Otherworld and anticipate soon governing the mortal one as well to its improvement or destruction. While there is no law that states that the Sidhe must rule, they gravitate toward roles of power and influence as naturally as they breathe and tend to end up with the reins of power even if they aren't looking to take them. The mandates of their goddess Danu weigh most heavily upon the Sidhe who are tasked with enforcing and imposing those rules on the rest of Fae society.
Long ago the Sidhe were able to work in the material world without any great deal of difficulty, but as humans have focused more and more on science and rationality, they have found that they can no longer do so, but must bond with a human being in a process known as Symbiosis. Functionally similar to demonic or angelic possession, the Sidhe merges its life force with that of a human (willing or not) and permanently integrates with that human being in mind and body. The result is a gestalt of the two beings, with the two minds becoming one.
There are rumors of some Fae that have the power to tear a Sidhe from their bonded host and banish the Sidhe back to the Otherworld.
This changeover forces the human host to undergo several cosmetic and physiological changes. First are the eyes. The eyes of a Sidhe are not like human eyes, being slitted like a cats or a snakes and having three irises - all of which are different colors or shades of the same color. The ears also change, growing slightly longer and coming to a tapered point. The body of the host becomes stronger, faster, more resilient and sturdier empowered by the Sidhe's supernatural essence. This bonding also makes the resulting fusion of matter and spirit immortal. Once the Sidhe has its human body that body is as immortal as the Sidhe itself and will endure the ages of the world without succumbing to aging.

The Sidhe in the World
The Sidhe are the only Fae in the Host that have to interact with the world like this and are the only Fae that are required to bond with a human being in order to work in the material world. The forces that define the parameters of reality are simply too hostile for the Sidhe to bear it. This bonding however also represents a permanent change for the Sidhe, being locked into a single physical body. While the Sidhe may have powers that allow it to change its shape, it will never again move beyond those constraints.
Because their inhumanity is so blatantly obvious, without the use of powers to mask their true shape, the Sidhe that are at large in the world tend to be secretive, furtive, taking great pains to mask their appearances. This is partly done to avoid attention, but also to reduce the chances of ensnaring mortal minds. The beauty of the Sidhe cannot be easily described, but it is known that when they draw on their powers and abilities they begin to glow faintly, and the more they draw on their powers the brighter this glow grows. This glow, which is known as The Shining, rapidly strips away illusions concealing the Sidhe's true appearance, and burns through clothing to reveal the Sidhe what they really are. The brighter the Shining is, the more beautiful the Sidhe becomes. Humans, and even some supernatural creatures close to humanity (lycanthropes, vampires, etc.) that see a Sidhe for what they truly are run the risk of becoming bespelled, or enthralled, by the Sidhe's beauty. The Sidhe refer to people so ensnared as being 'Elfshot' or 'Elfstruck' and tend to view the Sidhe as a love interest - with all the concomitant emotional entanglements and possible obsession.
The Kingdom of Concordia
The Kingdom of Concordia is the Kingdom of the Fae in the Otherworld that corresponds to the physical contiguous United States & Canada, and is the domain of King Absarinthe. The King has appointed Dukes which oversee territory roughly equivalent to the fifty states and the provinces of Canada, in addition to several Dukes which hold no specific fief but who act as his eyes and ears, and sometimes his fists and swords. For the purpose of the realm, the King Absarinthe is an NPC, but players are welcome to portray Dukes or lesser Nobles.
The state of Colorado is under the aegis of the Duke Finain ap Essus, a Sidhe noble of the Seelie Court.
Status in the U.S
Members of the Faerie Host are bound by to obey all the laws of the United States, and like other supernatural creatures fall under the jurisdiction of R.P.I.T. However, should R.P.I.T uncover criminal activity the accused Fae is tried under the appropriate criminal law and then remanded to the Courts of Faerie for punishment. The political landscape for the Fae resembles that of some native tribes, who are free to self-govern and enforce and impose their own laws. The Sidhe are anxious to make a good impression on their new-friends in the U.S and will likely deal with troublemakers harshly.