Duo is a member of the scavenger organization known as the Sweeper Group, which sent him to Earth to battle Oz. Despite the hardships he's suffered in his young life, and the seriousness of his mission, Duo is always cheerful and good-natured. But when he goes into battle as pilot of the Gundam Deathscythe, striking from the shadows with its lethal beam scythe, he truly earns his nickname "God of Death."

Duo, who seems perfectly happy not to have the fate of humanity resting on his shoulders anymore, has returned to civilian life as a scrap dealer. However, he still keeps in touch with his buddy Heero, and tags along on the grim hero's rescue mission to the space colony X-18999.