In the mirror universe, Lieutenant Ilia was a Deltan female in the service of the Imperial Starfleet of the Terran Empire during the 23rd century. In the early 2270s, she was the lover of Commander Willard Decker and served with him aboard the ISS Enterprise.
On the orders of his father Grand Admiral Matthew Decker, Will instructed three women - Janice Rand, Carolyn Palamas and Marla McGivers - to attempt to seduce Admiral Spock in the hope that one of them would become his mistress and they would have a spy in his inner circle. However, their efforts were fruitless.
Given that all three women were Terran as was Spock's wife Marlena Moreau, Decker believed that his plan might be more successful if Spock was offered something more exotic such as a Deltan. To that end, in 2272, he sent Ilia to rendezvous with Spock on the Enterprise's recreation deck. They sequestered themselves in one of the exercise pods and set it to private mode. After Ilia had disrobed, Spock told her that she was extremely beautiful and that her seduction pheromones were very potent even for a Deltan in her sexual prime. He then sent her away and she related the details of their encounter to Decker, with whom she proceeded to have sex.
Spock was able to resist Ilia's charms as most Vulcans were immune to Deltan pheromones. While observing Decker and Ilia via the Tantalus field, Spock explained to Marlena that he was already aware that they were lovers, as his agent T'Prynn supplied him with that information before returning to Vulcan. Spock chose to spare Decker's life on that occasion, as he believed that observing Decker's activities would prove valuable while eliminating him would tip their hand unnecessarily. However, Spock left Ilia's fate in Marlena's hands. At 0500 hours the next morning, Decker awoke to find that Ilia had vanished without a trace as so many of Spock's enemies had before her. (TOS - Mirror Universe novel: The Sorrows of Empire)
|ISS Enterprise (NCC-1701) personnel|
|Robert April • Phillip Boyce • Christine Chapel • Pavel Chekov • J. Mia Colt • Robert D'Amato • Willard Decker • Michael DeSalle • Fein • Finney • Karl Franz • Gaffney • David Garrovick • Hadley • Idelson • Ilia • James T. Kirk • Winston Kyle • Roger Lemli • Jabilo M'Benga • Leonard McCoy • Marla McGivers • Marlena Moreau • Number One • Carolyn Palamas • Elizabeth Palmer • Christopher Pike • Janice Rand • Kevin Riley • Saavik • Montgomery Scott • Elizabeth Sherwood • Solok • Spock • Stang • Hikaru Sulu • Nyota Uhura • Xon • Wu • unnamed ISS Enterprise personnel|