In the mirror universe, Lursa was a female Klingon who served the Klingon-Cardassian Alliance in the 24th century. Lursa was the daughter of Ja'rod, a member of the House of Duras and the sister of Duras and B'Etor. Her brother was named after their ancestor Duras, who served on the Klingon High Council during the late 23rd century.
She and B'Etor were frequent clients of the Sacred Chalice, a brothel run by Lwaxana Troi on Betazed. On one such visit in 2371, their bird-of-prey detected the Stargazer, a Terran Rebellion ship, in orbit of Betazed and destroyed it, killing everyone aboard including Lwaxana's eldest daughter Kestra Troi. Her younger daughter Deanna Troi, who had learned that Kestra was still alive only minutes earlier, became enraged upon hearing this. In her anger, she grabbed a small explosive device which the rebel spy Jean-Luc Picard had hidden on his person and threw it in the Duras sisters' direction. This ensuing explosion resulted in not only their deaths but that of Lwaxana as well. (TNG short story: "The Sacred Chalice") The sisters were survived by their brother Duras, who unbeknownst to them was an ally of Memory Omega. (TNG - Mirror Universe short story: "For Want of a Nail")