Duelo McFile is the ship doctor for the Nirvana. Duero quickly takes over medical emergencies often at the objection of the female pirates, but ignores them, assuring the crewmembers that he is not a threat. Since he is the only licensed medical practitioner on board the Nirvana, and being that the medical facilities on board the female pirate ship were no longer operational, the female pirates were left with no choice but to have him as their official doctor. A very calm and collected character, it was said that Duero got whatever job he wanted simply by submitting a blank resume with his name on it as he was one of Taraak's elite. However, he can be confused and awkward when faced with something outside of his experience and education, as when he had to coach Hibiki and Dita through delivery of Ezra's baby. While very analytical, he also makes an important discovery during the series regarding Hibiki's heritage. He eventually becomes close friends with Parfait, the first woman he worked closely with, which later develops into a mutual attraction. He fits the anime classification of a bishonen, randomly acts yaoi-like and never shows the right side of his face. The latter trait is explicitely referenced at the very end of the second season, when Paiway Underberg sneaks up to Duero and for a second, strokes aside the hair covering his right eye. She then contentedly exclaims "Just as I thought!" but because the audience only sees Duero's back at that moment, what she saw exactly remains a mystery(judging by the rather pleased faces both Paiway and Parfait had, he is probably handsome). He is voiced by Hideki Tasaka in the original Japanese dub, Steven Jay Blum in the English dub & Jefferson Utanes in Filipino dub.