Mili Skane is the daughter of a saddler from a village near Whitebridge. As a young girl, she went to the White Tower to become an Aes Sedai. When she discovered she couldn't channel, she became a Darkfriend. She was the assassin sent to kill Rand and Mat on their way to Caemlyn.
She is sharp-featured but pretty. Her face is delicate but vulpine. She has glossy brown hair that hangs below her shoulders and big brown eyes. 
Mili murdered Willim Avarhin and his daughter, Shiaine, and has taken on Shiaine's identity.
In Ebou Dar she was under the command of Old Cully and Jaichim Carridin to find the cache of ter'angreal, sa'angreal and angreal that was within the city. When Carridin spots Mat he instead places her in charge of finding and killing him.
Lady Shiaine takes up residence in Caemlyn with Falion Bhoda, who was given to Shiaine to use and punish for her failure in retrieving the angreal and ter'angreal stash in Ebou Dar. Falion is mostly used as a servant, as well as being given to Daved Hanlon, though the two merely exchange information. Shiaine also gives orders to Hanlon, sending him to the Royal Palace to become a guard and get close to Elayne. She also gave him the order to free the captive sul'dam in the palace and to burn Caemlyn's food warehouses.
Because of Shiaine's "easy" treatment of Failon, Murellin is asked by the dark one to come to Caemlyn and remind Shaiaine that Falion is her dog, in a manner unclear, but involving Murellin having use of Falion when Hanlon is not present. 
Eventually, Elayne, Vandene, Careane Fransi and Sareitha Tomares found her, along with Falion and Marillin Gemalphin, at Shiaine's house on Full Moon Street. Recognising them as Black Ajah and Darkfriends, Elayne and the other Aes Sedai attempted to capture them but were thwarted by the return of Asne Zeramene, Chesmal Emry, Eldrith Jhondar and Temaile Kinderode. Careane was revealed as Black Ajah, and the murderer of Ispan Shefar and Adeleas, Vandene's sister. Vandene killed Careane, but Asne killed Vandene as well as Sareitha.
The Black Ajah Sisters kidnapped Elayne from the city but she was rescued by Birgitte, who had felt the incident through her Warder bond, and the Windfinders at the Palace. Asne was killed in the fight and the rest of the Black Ajah sisters and Lady Shiaine were taken to the Royal Palace dungeons where they are currently being held.