Faeries (or Fey) fall into two organized courts: Summer Court (Seelie) and Winter Court (Unseelie). You will also find members of the race known as wyldfae (see the Muses at the Four Queens). To call either group good or evil just doesn’t work.
Each court is ruled by three: Queen Who Was (Mother), Queen Who Is (Current Queen), and Queen Who Is To Come (Lady), and while the Mother holds the greatest amount of power, she is bound by natural order, so she really cannot take an active part in ruling the Court. The Current Queen (presently, Mab for the Winter Court and Titania for the Summer Court) holds the most usable power in the Court, and she uses it to rule over her portion of the Nevernever. While the Lady may hold the smallest amount of power in the Court, she has the most freedom of action and is the most likely one you will see in the mortal world.
Faeries have successfully mated with mortals, and their offspring are known as Changelings. For frame of reference, Tina is a Changeling illusionist, and spends most of her time in the mortal world.
The Summer Court is most often associated with growth and heat, and has an obvious reign over the Las Vegas Valley. While most consider “growth” to be a natural thing, within Las Vegas, that growth has been population.
Typically, the Summer Court’s power waxes in and around the time of the Vernal Equinox (late March), and wanes around the first day of Autumn, however, occasionally, they will hold on to power for longer than expected, keeping fall days hot, occasionally into December.
As a direct contrast to the Summer Court, the Winter Court is responsible for decay and cold, both elements having seen an increase in the Las Vegas Valley in recent years. Many would just blame the recession for the loss of population, the loss of expansion, the loss of what the city once was; heck even the loss of Lake Mead. People in the know about the supernatural would beg to differ.
In the last few years, Las Vegas has seen more snow than in the previous few decades combined, and there is a reason why the valley was so hard hit by the current recession; the actual reason just isn’t published statistically. Facts become “facts”, and those who choose to believe them just accept the reasons without question.
The Winter Court has taken residence at the Venetian hotel, and currently employs the Goldsmith twins (Shane and Shawn) as their mortal emissaries, though their exact position has yet to be distinctly named.