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With his sister, Princess Quoi-Ling, they rule over the paradise planet. While both appear to be nineteen yahren old, Choi-Ling does not share his sister's elation at the arrival of the Warriors, and grows concerned as Starbuck uncovers information on how to counteract the gravitational field of the planet, as well as information that the residents of the planet are outcasts from Earth. In addition, only he and his sister know of Earth's location, but the Colonials fail to learn this.
Upon learning of their first attempt to escape, Choi-Ling orders that Starbuck and Apollo be imprisoned. However, their imprisonment is short-lived and they are able to escape the planet with Quoi-Ling, who has fallen blindly in love with Apollo. Upon leaving the planet, she rapidly ages and dies, and is thus the sole ruler of the planet (Island in the Sky).