From publisher blurb:
A paladin swearing the Oath of the Fairies binds themselves to an Archfey, a powerful creature who scoffs at the powers traditionally worshipped by mortal races. Though similar in terms of sheer magical ability, the Fey derive their power from a mixture of the arcane and raw emotion. The Archfey can be seen as unpredictable or temperamental, but a paladin sworn to their service typically feels a kindred spirit between them, and often sees logic where others see chaos (though others may perceive the paladin themselves as chaotic as well).
Expanding upon the mechanics of the 5E Paladin class, this PDF provides a new Oath option for paladins to pledge their services to the Archfey, gaining resistances to mind-altering magic and eerie powers from sylvan poetry. The PDF also contains the Feyborn background, compatible with characters of any class, representing those whose paths have already crossed with the Fey before becoming adventurers.