The Sarkoy are the people of the planet Sarkovy, featured in Star King and The Palace of Love, two of the Demon Princes novels of Jack Vance. Sarkoy mainly inhabit the steppes of their somewhat bleak and unforgiving planet.
Sarkoy have a highly formalised and structured society and place great value upon etiquette. A breach of certain manners may earn a death sentence; "dishonouring a fetish" is one such crime and "throwing sour milk upon his grandmother" is another (both offences quoted in The Palace of Love). The cruelty of the Sarkoy can be judged by the popularity of the sport of harbite, in which the harikap, a semi-intelligent animal, is tormented to death in a number of imaginative ways including being set on fire. (When Kirth Gersen ironically enquires of Sivij Suthiro what the Sarkoy will do for entertainment when they have exterminated the harikap, Suthiro responds blandly that they always have each other.)
Their most notable characteristic is that practically every inhabitant of the planet is skilled to a greater or lesser degree in the art of assassination by poison. An adept of this art is known as a venefice and it is rumoured that a Master Venefice can kill his quarry merely by walking past him. This may be an exaggeration, but perhaps not a flagrant one. Many venefices pride themselves on their ability to develop poisons out of substances previously considered harmless, and an expert can transmit toxins or plague germs on contact, even a contact so slight as to go unnoticed. A skilled venefice typically keeps his fingernails hardened and sharpened such that they can cut paper at a touch (in order to deliver subcutaneous poison); a still more skilled practitioner can poison one merely by passing him paper to show off this 'paper trick'.
In The Palace of Love Master Edelrod explains to Kirth Gersen that to avoid this fate a venefice will try to acquire immunity to the poisons that may be used against him and also exercises great caution in all his personal dealings (going so far as pre-emptively poisoning any rivals). In this way he will "live to become an old man" (a Sarkoy expression).