Star Trek Dark Passions Series 1-2 by Susan Wright

Star Trek : Dark Passions 1 - Susan Wright - Klingons and Cardassians rule the Alpha Quadrant in an uneasy alliance that hides a viper's nest of backstabbing plots and counterplots. Annika Hansen has become a trained operative for the Obsidian Order. Her latest target: Kira Nerys, the duplicitous Intendant of Bajor whose ruthless ambition has brought her to a position of power second only to the Regent himself, the fierce Klingon warrior known as Worf. To get close to her prey, Annika must worm her way into the Intendant's notoriously fickle affections. Easy enough to accomplish, perhaps, but it remains to be seen who is truly manipulating whom...

Star Trek : Dark Passions 2 - Susan Wright - Intendant Kira, now Overseer for the entire Klingon-Cardassian Alliance, has entered into a dangerous liaison with Annika Hansen, unaware that Hansen is actually an agent of the Obsidian Order who has orders to kill Kira when the time is right. But her treacherous alliance is not the only danger the Intendant faces. Both Deanna Troi, the power-hungry consort of Regent Worf, and B'Elanna Torres, the half-human Intendant of the Sol System, are threatened by Kira's unquenchable ambition, and would be glad to see her deposed -- or worse. As four powerful women scheme for control of the Alliance, who will survive? And who will claim the ultimate prize?