Qlippoth (singular & plural) are one of the many, many races of fiends that Pathfinder has chosen to create to further flesh out their array of evil outsiders, due to not being restricted to the Great Wheel.
The Qlippoth are the original inhabitants and masters of the Abyss, squamous and horrific creatures with shapes reminiscent of lower life forms such as insects and mollusks, and one of the two oldest races in existence, preceded perhaps only by the Proteans. Driven to near-extinction by the howling hordes of demons, they have become obsessed with the need to exterminate all mortal life in order to stem the tide of sins that give rise to their rivals. Presumably once they're done with this they'll return to their old larger goal, which seemed to be the destruction of all existence outside of Qlippoth and the Abyss.
They're essentially the Pathfinder equivalent of D&D's Obyrith.
|The Fiends of Pathfinder|
|Lawful:||Asuras - Devils - Kytons - Rakshasas|
|Neutral:||Daemons - Divs - Sahkils|
|Chaotic:||Demodands - Demons - Qlippoth|
|Lords:||Archdevils - Four Horsemen - Ahriman - Demon Princes|