From The Heretic Knowledge Vault
The Ralkin inhabit the Southern Continent, where they are the arch-enemies of the tribe of kobolds that includes player character Tamina and her friends. As far as can be told, they are themselves human, albeit with some decidedly inhuman (or at least inhumane) behaviors. At the minimum, they seem to have a particularly nasty set of magical skills that create great pestilence among the kobolds and the nearby human town of Grendell.
Tamina and fellow PC Jamie fall afoul of this unpleasant bunch when they travel to the Southern Continent to avoid the attention of other undesirables (not to mention Jamie's mother, who may not be "undesirable" per se but certainly makes a pest of herself). After numerous adventures that involve plagues, polymorphs, and of course violence, our heroes (heroines?) triumph, then wisely get out of the area. Whether we've seen the last of the Ralkin is unknown at this point.