Cassandra

"I must go," Cassandra said. "Before the night is over, you may wish you were being sacrificed." She looked from Gabriel to Raina. "A slit throat would be quicker." I agreed with her, but I wasn't sure what to say. We were discussing different ways to kill me. None of them seemed particularly good choices.

(The Killing Dance, page 360, paragraph 5)

* She was in love with Sabin, but could not accept his need to drink blood. She wanted him to stop, and he did. But because of his choice, half his body began to rot. They had to seek Anita's help in the hopes of her healing Sabin, but they did not tell her they were part of a triumvirate. Cassandra was simply a visiting werewolf.

* As an alpha werewolf, Cassandra intimated to Anita that she was seeking the position of Lupa when she came to St. Louis, but acknowledged that Anita already held that position.

* Cassandra has a master's degree in magical theory and mentioned it when she was able to reveal some knowledge of necromancy during the time that Anita raised the vampires Willie, Liv and Damian in the daytime.

* Because of Sabin's condition, the only way to preserve the triumvirate was to either heal Sabin somehow or hope that Dominic's spells could keep his insanity locked up. Because otherwise, if the Vampire Council must kill him, they would kill Cassandra and Dominic as well.

* Their triumvirate had a deal with Marcus and Raina. The lycanthropes were supposed to kill off Anita. They failed.

* When Edward shot Dominic, Cassandra attacked him. Harley then attacked her and shot her dead.