The egotistical and typically chauvinist leader of the Kazon's Nistrim sect, Culluh dreamed of reviving his fading people's claim to power among the chaotic Kazon Collective and saw the Voyager defector Seska as his chance.

Taking her as his consort, Culluh was stern with his ambitious Cardassian mate in public, but privately allowed her full reign to advise him and plan tactics — including the conquest of Voyager. Still he was too arrogant to utilize her advice — overplaying his hand and destroying a peace overture from Voyager's Capt. Janeway, allowing the kidnapped Chakotay to escape in another. He lived to see Voyager's takeover, though, only to lose it after dropping his guard. Seska was killed in the loss of the ship, but he escaped with their infant son, whom she had believed to be fathered by Chakotay. Culluh likely never knew Chakotay and his mate had once been lovers in the Maquis, since Seska had told him she was raped.