Princess Erzsé and her pet Rebecka. The Princess is heiress to the Crown of the Three Sisters. The Three Sisters are the planets Isis, Rhea, and Anu in the isolationist Hestia system. Rebecka is a nuppa, the native people of Isis. The Sisterhood had enslaved the nuppa generations ago.
Both the Sisterhood and the nuppa are a “selected species.” They are clones or conceived artificially. All Sisters and nuppa are female.
