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Raul Endymion is the primary protagonist of the novels Endymion and The Rise of Endymion. He is also the narrator of the novels, telling the story from his Schrodinger cat box prison in orbit around the quarantined world of Armaghast.
Raul is introduced as a hunting guide on Hyperion, where early on he is accused of murder (although his victim was "reborn" via the Cruciform). Raul is spared his execution by Martin Silenus and is hired by the poet to find Aenea and uncover the TechnoCore's current agenda. Raul is joined on his journey by A. Bettik, an android introduced in Hyperion.
As Raul states in the beginning of his story, his first name is pronounced like "Saul" or "Paul," as opposed to Raoul, which has two syllables.
By the time of the novels, Endymion has become Aenea's romantic interest, and eventually becomes her lover. His story completes the Silenus' Cantos.