Fairies, or fey, are the odd-ones-out of the three major magical races. They seem to defy most of the conventions that the other two regard as a solemn law.
Firstly, while dwarves and elves do not breed with humans, (or each other!), fey seem to make a past time out of it. Rural villages will frequently have tales of young ladies and men lured into the woods by an ellusive, shimmering figure and families across the continent might display an unusual energy that betrays a union with one of the fair folk. Nobility attempts to trace lineage to avoid this, but since even the most violent of the fey still has a capability to attract members of the opposite sex, the common people have little protection.
Secondly, a dwarf is a dwarf and an elf is an elf, though they may display certain regional differences, they are essentially the same race across the world. Not so with fairies. The fey demosntrate such a wide varience of capabilities and attitudes that they are often regarded as simple magical abberations unrelated to the rest of the world at large. Most fey, but not all, are able to either turn invisible at will or transport themselves freely within a certain area. This translates to crossbreeds as a capability for stealth or speed. Half-fey spies are much sought after, despite their being frowned on officially. Fey will often seek out magic users to sleep with and the children are often extremely powerful, if they survive the attentions of certain religious institutions.
Geographically, fey are everywhere, though they seem most comfortable in remote areas where they can take advantage of human superstitions. The forests of Germany and England are favourite haunts, while Ireland and Wales are practically infested with them.
Many scholars have attempted to devine what it is fairies sustain themselves on, (half-breeds seem to survive mostly on human fair) a subject that the fair folk seem very tight lipped about…