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Demi is a female android created by Wren to assist in managing the environmental control systems of Motavia. Her primary duty is to oversee the operations of Nurvus. From that facility, she is able to remotely operate portions of the Motavia control systems.
When Zio began attacking Motavia, he captured Demi and created a fortress on top of Nurvus. She remained his prisoner until rescued by Alys Brangwin and her companions. Following Alys' subsequent affliction with the Black Energy Wave, Demi joined the group in search of a way to defeat Zio. When that task was accomplished, the diminutive android interfaced with Nurvus directly in order to regain control of the environmental systems running amok.