Book 1: Swordspoint
Ellen Kushner (1987)

On the treacherous streets of Riverside, a man lives and dies by the sword. Even the nobles on the Hill turn to duels to settle their disputes. Within this elite, dangerous world, Richard St. Vier is the undisputed master, as skilled as he is ruthless–until a death by the sword is met with outrage instead of awe, and the city discovers that the line between hero and villain can be altered in the blink of an eye.

Book 2: The Privilege of the Sword
Ellen Kushner (2006)

Katherine, is a well-bred country girl versed in the rules of conventional society. Her mistake is thinking that they apply in Riverside. For Katherine’s host and uncle, Alec Campion, aka the Mad Duke Tremontaine, is in charge here—and to him, rules are made to be broken. When Alec decides it would be more amusing for his niece to learn swordplay than to follow the usual path to marriage, her world changes forever. Blade in hand, it’s up to Katherine to navigate a maze of secrets and scoundrels and to gain the self-discovery that comes to those who master: the privilege of the sword.