William Orwell, originally called Acqua of the Back (or Acqua of the Rear in certain translations), operates as a mercenary and ex-member of God's Right Seat under the Roman Catholic Church. Born in England and baptized Anglican, his latent Saint potential fully awakened within God's Right Seat. This granted him "Divine Mother's Mercy," aligning him with Archangel Gabriel and amplifying his magic. His bond with Gabriel reflects in his habitual blue attire. Before joining God's Right Seat, William worked globally as a lone-wolf mercenary, prioritizing missions benefiting Great Britain. He maintained ties to the British Royal Family and befriended the Knight Leader, leading to a knighthood offer. Though he designed a personal escutcheon with mythological creatures, he declined induction due to distrust of the institution’s corruption and political maneuvering by figures like Laura Stuart. He instead chose to externally protect Britain while the Knight Leader handled internal security. His solo resolution of the Princess Villian hostage crisis—rescuing her from the Spanish Astrological Sect after political obstruction neutralized England’s Knights—exemplifies this role. As "Acqua of the Back," symbolizing water and Gabriel’s domain, William adheres to a strict ethical code: avoiding civilian casualties, despising looting, and respecting courageous foes. He offered Touma Kamijou honorable surrender terms during their clash and executed Terra of the Left for exploiting civilians, including children, for magical adjustments. Despite his God's Right Seat affiliation, he retains loyalty to England and deference to the Pope. During the Academy City conflict, Acqua directly targets Touma Kamijou, formally challenging both the Anglican Church and Academy City. His combat prowess—augmented by Saint physiology, Divine Mother’s Mercy, and God’s Right Seat enhancements—overwhelms Touma, the Amakusa Christians, and Academy City’s technology. However, he harbors a critical vulnerability: magic countering Saints, especially when combined with crucifixion symbols like crosses or thorns. This flaw is exploited in his final battle, where Kanzaki Kaori, the Amakusa’s "Saint Destroyer" spell, and Touma’s intervention defeat him. He accepts this loss graciously, without resentment. After defeat, William surrenders and is imprisoned in the Tower of London. Post–World War III and God's Right Seat’s dissolution, he discards the "Acqua" alias, reverting to William Orwell. He collaborates with former enemies without grudges, and his escutcheon remains preserved in Buckingham Palace as recognition of his service to Britain.