Elves are a type of Faerie folk. That is to say, "Faerie" encompasses a wide range of humanoid fair-folk from Goblins, Pixies and Dwarves to of course, Fairies. It is sometimes said that the insect-winged Fairy even descend from the Alfar, the oldest race of Elves native to the world where Kellwood lies, though most Fairy will heavily contest this as mere rumor.
Elves from other lands can be found in Kellwood as well. Elves typically have pointed ears, and features that many may consider attractive. In human cultures, it was warned that Elves posed a danger of seduction and could lead men and women astray with their wiles. Perhaps this is true, there are a number of half-elf hybrids in Kellwood.
Welfs are a supposed hybrid of Elves, but the (retroactively) derogatorily named "Rat Elf" is not of Elfin ancestry. There is no standard size of Elf in Kellwood, in fact there is a rather large gamut of Elf folk. From tiny, to dwarf-like, to very tall. Elves typically have skin tones closer to those of humans-- from rich dark tones to ghost paleness, as opposed to the strange hues of their cousins the Fairies. Elves subsequently have an easier time passing for human should they find themselves in the realms of "Mankind".
Elves, much like other Fae races, possess their own innate magics which they may use to cast glamour on objects or use to hide themselves from mortal eyes. In deepest Kellwood, such trickery is almost unknown-- among their own kind it is considered rude, and there are no human mortals to deceive deep in the land of Kellwood. Instead, they work their magics mostly into trinkets, ravals, and simulacrums of human objects in the Silver Forge. Elves can also easily tell when an object is under a glamour spell.
The kingdom of the Elves is called Eldenlon, and it is ruled by King Malachai Porter and Queen Hazelle. Elves, much like the Fairies and Dragons, have a fascination with the human world in Kellwood and consume as much alleged human media and merchandise as possible. Due to their close ties to Dragons whose territory overlaps with the Human City, they have a direct distributor of these goods.