Leo Aiolia (known as Ioria di Leo in Italian) stands as the Gold Saint guarding the Sanctuary's fifth house of Leo. As the younger brother of Sagittarius Aiolos, falsely condemned as a traitor for saving the infant Athena from the corrupted Pope's assassination attempt, Aiolia carries this heavy legacy. It drives his fierce determination to prove loyalty to Athena while privately honoring his brother. This inner conflict led him, in his youth, to dye his naturally blond hair red to distance himself from the disgrace, though he maintained profound love and respect for Aiolos. Aiolia first confronts the protagonists during the Sanctuary arc, dispatched by the Pope to retrieve the Sagittarius Gold Cloth from Saori Kido (Athena's reincarnation) and eliminate her Bronze Saints. In Japan, witnessing the Sagittarius Cloth awaken to protect Pegasus Seiya and a vision of Aiolos' spirit affirming Seiya's role shatters Aiolia's conviction. After Saori reveals her identity and the Pope's deception, Aiolia pledges loyalty to her but returns to the Sanctuary to confront the Pope. There, the Pope ensnares him with the "Demon Emperor Fist," a mind-control technique forcing him to attack the Bronze Saints at the Leo Temple. Cassios's sacrificial intervention saves Seiya and breaks the spell, freeing Aiolia to join Athena's cause. Years prior, chronicled in *Saint Seiya: Episode G*, Aiolia battled the Titans invading the Sanctuary. His combat prowess and lightning-based cosmos attract Titans like Pontos and Hyperion, who brand him the "man of Evil Omen." Recalling his brother's guidance, he develops the forbidden technique "Photon Burst" to defeat the Titan Koios. This complex attack involves emitting photon stars (Photon Invoke), enveloping the opponent (Cosmos Open), infiltrating their body (Photon Drive), and triggering an internal explosion (Photon Burst). He dedicates this technique, created to protect loved ones, to his brother. His signature attack remains "Lightning Plasma," unleashing millions of light-speed punches capable of shredding armor or forming defensive grids. In *The Hades Chapter - Inferno*, Aiolia enters the Underworld with Athena and fellow Gold Saints to confront Hades. Within Hades' Castle, Hades' cosmic influence drastically reduces his power. Wyvern Rhadamanthys, one of Hades' Judges, easily overpowers Aiolia, Mu, and Milo, casting them into Cocytus. Athena later resurrects and frees them in Elysium. At the Wailing Wall, the barrier to Hades' inner sanctum, Aiolia joins the other Gold Saints in a final sacrifice. They channel their collective cosmos through the Gold Cloths, destroying the wall to enable the Bronze Saints' passage, cementing his martyrdom. Aiolia reappears resurrected in Asgard in *Soul of Gold* by unknown forces. He allies with Lyfia, a maidservant of Queen Hilda, uncovering the god Loki's plot to dominate Asgard. Reuniting with other Gold Saints, Aiolia temporarily awakens his Gold Cloth into a God Cloth through heightened cosmos. Chosen to wield the Cloth of Odin, he ultimately defeats Loki using Odin's sword, aided by Athena's divine intervention. Before vanishing, he gives Lyfia a protective necklace. His journey transforms him from a conflicted warrior burdened by betrayal into a resolute protector of Athena. His combat style emphasizes speed and lightning-based attacks, reflecting his loyalty and sacrificial nature. Relationships with allies, including the close friendship with Virgo Shaka and the frequent ideological counterpart Aries Mu, further shape his unwavering commitment to justice.