The Fey
The Fey is an umbrella term to refer to those inhabitants of the Feywild who are native to that realm. They range in appearance from hideous hags to mysterious darklings to the beautiful eladrin. The least among them were no more powerful than mortal goblins, while the greatest nearly godlike in power.
Society
The Fey tended towards chaotic, and their society was as wild and shifting as the land they inhabited. There were, however, some constants. The Archfey ruled regions that seemed to reflect their character, or perhaps they took on the traits of their realms. The Summer Lord's kingdom was a land of sum and and wild revelry, while the Queen of Air and Darkness's court was a place of eternal winter. Various fey lords and ladies ruled smaller realms, either in service to one of the Archfey or else attempting to avoid their attentions.
Some Fey, like the Lord of the Hunt or the Prince of Fools embraced the wild and chaos of their land, respecting no rulers and prowling the wild land for their own ends and amusement. Others built formal noble courts whose extravagance and intricacy put those of the mortal realm to shame, with Fey knights competing in elaborate tournaments for strange prizes and glory.
Culture
Time in the Feywild passes strangely (or not at all). Even little boggles might live for centuries if they are lucky, and the greater Fey have lived for millennia or longer. Their interactions with each other involve eternal grudges or thousand-year-old favors, and can seem incomprehensible to outsiders.
Fey are frequently bound by ancient and magical oaths, obligations, curses, and compulsions. A carelessly chosen word might drive a fey into a homicidal fury or bind them to the speaker for service. The true names of the Fey can give those who know them great power over those named, so it is customary for they Fey to give false names or go by sobriquets.
They are great lovers of beauty, both artistic and natural, though beauty can sometimes be in the eye of the beholder.
The Fey are particularly hostile to fiends, beings of the Shadowfell, and creatures of the Outer Dark.