Demon Nemesis rules the brown dwarf Nemesis, just outside our system, and is responsible for dark matter which comprises roughly 80% of the universe. He put himself up for stakes in a game to save Earth from Fornax. He developed an interest in Fornax in the years following. Astrid gave Fornax the idea to marry him, and they adopt Santo. Though he is not happy about the arrangement, he takes his responsibility seriously and defends Santo.