The mirror-universe Nog inherits the bar on Terok Nor after his uncle and father are killed, and repays the Intendant for that good fortune by setting her free, only to be shot by her.
The mirror counterpart of Nog appears in the fourth-season episode Shattered Mirror. With the mirror Quark and Rom both dead, the young Ferengi has ended up running the bar on Terok Nor, now held by the Terran rebels.
Unlike the Nog of the prime universe he has no interest in duty or in the rebel cause. He is openly grateful to Intendant Kira, reasoning that her executions of his uncle and his father are what handed him the business, and when the station comes under attack he releases her from the brig.
His reward is brief. Once he has helped her get away, the Intendant decides he is a loose end and kills him, shortly before her confrontation with Jake Sisko and the mirror Jennifer.