Ok, Here goes: (sorry in advance for my bad english)
Ëfrilith is known as a race of theives, or chameleons as they also are called, that steals anything they can get their hands on. They are in no way selfevolving, as they steal not only objects and items but also memories and thoughts. For example in shape of books or personal letters from perhaps a husband to his whife. It is said that they live in mazes under the big roots of the trees in Fangorn Forrest. If you´ve ever encounted boobytraps in the depths of the forrest, you know they are close. Other species know them as hermits and because they dont have a true identity, little is known about these masked creatures as their true faces never been revealed, nor is it known how many of them is still out there. There are no records to be shown that even one of them have ever been captured. Some say that they are just a myth…
As they have a similar anatomy of orcs, humans and hobbits as well, they are perfect chameleons when dressed appropriate. They can then easely blend into crowds of people or other illfigured beings. Their height vary. It´s said that they´re taller than hobbits, but shorter than humans and with a constant crouched posture. They´re lithe and muscular, but sinewy, in that way a perfect athletic theif.
Ever since The One Ring was found by Smegol, the Ëfrilihts thirst to posess it. It´s said that they´re out there, searching for The One Ring. It´s the ultimate theft, their one goal…