Sunni Moon, the mirror universe counterpart of Sunni Moon, was a "free agent"--an assassin, mercenary, Stephen April's personal "hit-woman" and one of his several lovers. She was also, simply put, crazy--a psychotic, murdering maniac who took care of the "dirty deeds" for April, acting as his "long arm" in dealings with others.
In 2385 Sunni's twin sister, Kitti, an agent of the Klingon-Cardassian Alliance, infiltrated the ISS Arcadia, passing herself off as Sunni in an attempt to assassinate April, but failed and was killed by Tabatha Brisk, for which Sunni longed to "get even". Sunni jealously hated Eve Ordalani, who goaded her in a constant rivalry.
- On Star Trek: New Empire, real-life actors' images were used to simulate characters. In this sense Sunni was "played" by actress Sheri Moon (after whom she was named).
- The original character of Sunni Moon was based on Sheri Moon's portrayal of "Baby Firefly" in the Rob Zombie film House of 1000 Corpses. As such, she displayed many of the character's comedic elements. Her mirror universe counterpart essentialized her dark, criminal streak, as (more evidently) seen in the sequel, The Devil's Rejects.
- The name of her twin sister, "Kitti", originated from one of Sheri Moon's credited stage names . The variant spelling was a form of tribute to the Canadian rock band Kittie.
- The character of "Kitti", the twin sister, arose as a retcon explanation after Tabatha Brisk killed mirror-Sunni for trying to assassinate Stephen April. "Sunni" was kept around out of love for the character.