The Darklings - A Monster Race

Darklings are monstrous human-like creatures that dwell in deep forests and caves, known to be tribes of cannibals that desire to eat human flesh raw. It is believed that they are humans who have forgotten the faces of their ancestors (an old Xythian turn of phrase that means someone is acting/behaving inappropriately or shamefully). Children are often threatened with “being left out in the woods for the Darklings to eat!” to deter bad behavior. 
These bestial creatures are rumored to exist in different varieties - green, grey and purple - some say the green ones are the size of a gnome, while the purple are bigger than the largest of men. No one has ever seen a female Darkling.
Sages and Arcanists who study such matters believe the Darklings are spawned directly from the legendary Darkswell, reported to be located in deep, dangerous, underground caverns.
There is a bawdy tavern song about a lonely young Shepherd searching the hills for a lost goat who discovers a female Darkling of surpassing beauty, with pale blue skin. She seduces him, with music, songs and kisses, to return to her lair for a night of passion, only for the young man to awaken in the wee hours, tied to a spit and roasting over a fire.
The sages speculate the origin of this song is based on an attack by a succubus.