D'Sefet was the Caitian Starfleet commanding officer of Federation Installation Nine and the USS Bastet. His friends called him Sef. (D'Sefet's Cat House, the logs of Federation Installation Nine‎) D'Sefet was born on 31 October 2246 and joined Starfleet in 2264, serving as a cadet under Captain James T. Kirk aboard the USS Enterprise. He remained aboard the Shadow Hawk during the Dominion War, rising in the ranks from a joint communications/tactical officer role to the executive officer of the vessel.