Kasei is the child of John Boone and Hiroko Ai. Kasei, and the other children, were created in vitro, with eggs from the fifty women on Ares, and fertilized with the sperm samples of the men on Ares. Children were created from all the samples, resulting in a ready made colony for Hiroko. Kasi visits John one evening to warn him about the fight against the transnational corporations.