Lomus was a Sheyang mercenary, and second-in-command to Teurac. He was aggressive and ambitious -- often to his own detriment. When they encountered Moya and the Zelbinion, Lomus was eager to attack despite Teurac's reservations. He wrested commend of the crew from Teurac and attacked anyways -- though Teurac was suspicious that Ka D'Argo had laid some kind of trap. The attack failed thanks to the reactivation of the Zelbinion's defense screen.
After his failure, Lomus returned command to Teurac and was ordered to lead a team aboard the Zelbinion to take it by force. Thanks to the shifting holes in the malfunctioning defense screen, Lomus was the only member of his team to survive to board the command carrier. There, he encountered Aeryn Sun, who narrowly avoided being roasted alive by one of Lomus' fireballs. Then, he discovered Gilina Renaez and John Crichton. As he prepared to kill them with another fireball, Aeryn shot him -- causing him to explode.
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Lomus is derived from Farscape.