She is six feet tall, pale skin, dark hair, shiny highlights, beautiful face despite the obvious arrogance. She walked with a predator's prowl and grace. She feeds off lust, and her behaviors and actions are dictated by her Hunger. Feeding is a natural reflex for her. She thinks she should get to feed on anyone she wants, anytime, anywhere. Her Hunger controls her completely. According to Thomas, Lara is tired of cleaning up after her.
Madeline is suspected of working as a puppet for the Black Council, although there is no confirmation. She tracked Harry Dresden using a private investigator in order to discover Morgan's location. Madeline is later killed and eaten by Lara Raith.
In the seriesEdit
Madeline is first mentioned in Blood Rites, when Lara Raith cuts Thomas off from the protection of House Raith, including financial support, he questions if it was the Twins idea. Lara says it was Madrigal Raith who pressed her into it but Madeline didn't particularly care.
In Turn Coat, Madeline makes a vampy entrance through Zero. When she threatens Justine, Thomas breaks a metal chair over her head, then pins her to a table and lets Justine kiss Madeline's forehead, burning the flesh while Madeline screams. Thomas tells Dresden their House has firm rules on poaching, Madeline deserved it, and she had to be shown.
It comes out that Madeline had tampered with the mind of Evelyn Derek and paid her to hire a detective, and sent the hitman Binder and his Grey Suits after Dresden. And she most likely sent "Shagnasty", the Naagloshii to the Raith estate suspecting that Dresden and Anastasia Luccio were telling Lara Raith information that would finger her. Dresden brought it to Lara's attention. 
On Demonreach, Madeline and Binder attack the Council with Grey Men. She subdues Dresden with her White vampire mojo, then nearly shoots him in the head. William Borden and Georgia stop her and take her on. They scatter when Dresden warns them of Binder and his gun. She goes for Dresden who shoots her several times, but she keeps coming. She is stopped and killed by Lara Raith. Madeline affected Will Borden and Georgia in a way that took them out of the battle, but didn't harm them in the long run.