Kysandra is first enountered as a seventeen year old girl living with her mother on Blair Farm, her father having been killed three years previously when on a sweep after a Fall. She has freckles and auburn hair (sometimes described as red), often worn in a braid.
She meets Nigel Sheldon, who takes pity on her and grows to love in a paternal way, and so reactivates her Higher functions (as she is descended from a Higher of the Brandt Dynasty), including giving her knowledge of the universe outside the Void and the civilisation and technology of the Commonwealth. Nigel also shows her the ability of the Void to reset itself to a previous configuration, such as was used by Edeard. But Nigel can only go back a few seconds or a couple of minutes at the most.
Kysandra aids Laura Brandt in her fight against the Prime invasion of Bienvenido, even though Slvasta still thinks she is an agent of the Fallers, if not a Faller herself. In this book we learn that Kysandra has become known as the Warrior Angel after one of Sheldon's ANAdroids (Fergus) says of her "She may look like an angel, but she can be quite the warrior when she needs to be." Later in the book, in the time of Chiang, she has passed into legend, with some people believing that she does not really exist, but is either a children's story or propaganda promulgated by the Eliters.