Peretor Sain was a native of Mordan IV who lived during its civil war. He was responsible for the assassination of Karnas' father, a move which prompted Karnas to turn to Starfleet for support and to request weapons. Mark Jameson accepted the request and supplied Karnas's forces with advanced weaponry which prolonged the war and caused immense suffering.

In 2364, Jameson reminded Karnas of this when attempting to convince him that he was who he claimed to be. (TNG: "Too Short a Season")

This character was only mentioned in dialogue.