Fey

They are a race that have gone by many names throughout history; to their closest friends, the Altharadi elves, they are "daoisaeg", or clever folk. The humans call them "fairies" or "pixies", which often depends on whether their actions are friendly or malicious. But tales of their exploits almost all refer to them as simply "The Fey."
At some point in time, no one really knows when, the veil separating the confusing assortment of fey realms known collectively as the Twilight Lands and the Material Plane was breached in several places across the world. One of those breaches appeared in the Woods of Nualoth, in the lands of the Rhovegnos, where the fey had their first encounter with beings from the Material Plane. The Rhovegnos Elves had a naturally curiosity for all things magical, so were consequently delighted and fascinated to meet these beings of pure magical essence. The fey were shy at first, and so those early encounters were brief. But as more and more of the fey started to venture out and explore the Material Plane, a bond between the two races started to flower, to the point where Elves were even invited to explore the fey realms.

Races of the Fey
After however many hundreds of years it has been since that first encounter, the fey have become an increasingly frequent sight, at least in Altharad. Elven scholars theorise that the forms they most often assume; fairies, pixies, nymphs, dryads and changelings, are a direct result of their exposure to, and interpretation of, the Material Plane.

Fey Physiology and their interactions with the Mortal Realm

A stereotype which often features in elven and some human literature depicts the fey as possessing relentless sexual energy. Whether its changelings assuming an erotic appearance to seduce gallant paladins, nymphs luring naïve young stablehands into the woods where they might have their wicked way with them or fairies holding midnight forest orgies with all manner of critters, the overriding message tells of a race which have no comprehension of the sexual norms of most Material Plane races. The Elves have, as delicately as possible, made inquiries about this with their fey friends.
What is quickly apparent is that the cycle of life and death is wildly different in the fey realms than it is in the Material Plane. Fey do not ascend to another realm of existence when they die. Instead, after a fey decides that they have fulfilled their current life cycle, they will willingly allow their "essence" to dissolve back into the fabric of their home realm. It is possible to kill a fey within the fey realm, but that ability is limited to the inexplicable King of the Fey, and even then, he will not carry out a sentence of execution unless all the fey of that realm agree. As a result, only two entities have ever been executed across the entire collective memory of the fey.
Fey do not reproduce in a way that we would understand either. When two or more fey come together and share a moment which triggers strong emotions such as joy or exhilaration, their bonded essences will seep into the fabric of their fey realm, triggering the creation of a new fey entity shaped by those emotions. This bonding experience can take many different forms; a pair of fey might play in a meadow for a day, or a group might meet and hold hands and sing throughout the night. Of course, the creation of a new fey entity might well be the result of an immense, frenzied orgy, but sex is not a prerequisite for the creation of a new fey.
The act of sex, it seems, is in fact an alien concept to the fey, one they have only come to understand a result of their exposure to the Material Plane. However, it is a habit they have enthusiastically embraced. Fey feel all things far more strongly than mortals, so it is no surprise they would come to enjoy the experience of sexual pleasure. As a consequence, those with prudish natures should beware before setting foot in the Twilight Lands. One can scarcely go two feet through the fey realms without seeing a stag with luminous antlers mounting a lioness with five tails and a serpent's tongue, or a collection of pixies gathered on the lap of a satyr to pleasure it. Fey share sexual favours in the same way that humans share stories, and should they happen to come across anything so wondrous as an actual mortal from the Material Plane, they are likely to proposition that mortal as a form of greeting.
Because of this, many fey find it difficult to adjust to the realities of the Material Plane. Those fey that do visit often do so in the company of elves or other mortal beings who can act as escorts and advisers. Some of course spend months or even years in the Material Plane, and will in time come to change their approach when interacting with mortals, but in the back of their minds they will find such behaviours illogical; "Why does it matter if you take a loaf of bread from a mortal's market stall without giving them coin in exchange, when they pluck a flower from the ground and ask it nicely to turn into a new loaf of bread?" "There is no need to bring the horse back after borrowing it; just make friends with another one, maybe they'll take you where you need to go." "What is wrong about having sex with two dwarf twins and a lovely half-orc lady in this fountain in the middle of the city square?"