Leo Aiolia is the Gold Saint of Leo, guardian of Athena's Sanctuary's fifth temple. He bears the heavy legacy of his older brother, Sagittarius Aiolos, who was falsely condemned as a traitor for attempting to assassinate the infant Athena. This accusation tarnished Aiolia's standing, compelling him to prove his unwavering loyalty to Athena and cleanse his family's honor. Though he initially accepted the verdict of his brother's betrayal, he privately held deep respect for Aiolos's memory. This inner conflict led him, as depicted in "Saint Seiya: Episode G," to dye his naturally blond hair red during his youth, symbolically distancing himself from the disgrace while still harboring profound love for his brother. Aiolia possesses an impetuous and fiercely passionate nature, often driving him to swift action. This temperament sometimes creates friction with more reserved Gold Saints like Aries Mu, though he shares a close bond with Virgo Shaka. Recognized for his exceptional combat prowess and sense of justice, he is sometimes called the reincarnation of the legendary hero Achilles. His combat abilities center around lightning-based techniques propelled by his mastery of the Seventh Sense, enabling movement and attacks at light speed. His signature moves include "Lightning Plasma," unleashing billions of plasma projectiles per second, and "Lightning Bolt," a concentrated energy blast. In "Episode G," he develops advanced techniques like "Lightning Fang" and the immensely powerful "Photon Burst," which releases explosive photons inside an opponent's body. He also demonstrates telekinesis and, in anime adaptations, healing capabilities through cosmic energy manipulation. Introduced in the original Sanctuary arc, Aiolia was dispatched by the false Pope (Gemini Saga in disguise) to retrieve the Sagittarius Gold Cloth and eliminate Saori Kido (Athena) and her Bronze Saints in Japan. Confronting Pegasus Seiya, he critically injured Ophiuchus Shaina when she shielded Seiya. Witnessing the Sagittarius Cloth protect Seiya and experiencing a vision of his brother affirming Seiya's role as Athena's true protector led Aiolia to question the Pope's motives. Returning to Sanctuary to confront the Pope, he fell victim to Saga's "Demon Emperor Fist," a mind-control technique. Forced to guard the Leo Temple against the invading Bronze Saints, his controlled state manifested sadistic tendencies, slowly tormenting Seiya. The spell was broken when Cassios sacrificed himself, taking Aiolia's "Lightning Plasma" meant for Seiya. Freed from control, Aiolia pledged his loyalty to Athena once her identity and his brother's innocence were confirmed. In "The Hades Chapter - Sanctuary," Aiolia played a crucial role during the invasion by Hades' forces. He witnessed Virgo Shaka's sacrifice via the Athena Exclamation, performed by the resurrected Gemini Saga, Aquarius Camus, and Capricorn Shura. Enraged by their perceived betrayal and Shaka's death, Aiolia immediately attacked the trio alongside Mu and Scorpio Milo. This confrontation escalated into a catastrophic clash of dual Athena Exclamations, which destroyed the Virgo Temple before the combined efforts of the Bronze Saints diverted the energy skyward. Following Athena's subsequent suicide to reach the Underworld, Aiolia, Mu, and Milo pursued Saga, Camus, and Shura to Hades' castle. There, they faced Wyvern Rhadamanthys but were severely handicapped; Hades' barrier reduced their power to one-tenth. Rhadamanthys effortlessly defeated them and cast them into Cocytus, the frozen abyss of Hell. Athena later resurrected and freed Aiolia and the others upon her arrival in the Underworld. He participated in the final assault on the Wailing Wall, the barrier blocking entry to Elysium. Recognizing the necessity of the sacrifice, he joined the other Gold Saints in converging their spirits at the Wall. They willingly destroyed their physical bodies and Golden Cloths to create a single, universe-big bang-level impact, successfully breaching the Wall and allowing the Bronze Saints passage to challenge Hades directly in Elysium. Following the Hades conflict, Aiolia was temporarily resurrected in Asgard during "Soul of Gold." Disoriented after awakening, he encountered Lyfia, a maidservant to Queen Hilda. Learning of the malevolent influence corrupting Asgard, he prioritized protecting Lyfia and investigating the disturbance over immediately returning to Athena's ongoing battle. Reuniting with the other Gold Saints, he discovered the Asgardian god Loki sought a powerful weapon to dominate the realms. Aiolia was chosen to wield the divine Odin Robe. Empowered by Athena's blood-stained petals, he attained a God Cloth and ultimately delivered the decisive blow against Loki, restoring peace to Asgard. Before vanishing, he gifted Lyfia a necklace as a token of his enduring protection. His character arc culminates in "Saint Seiya: Next Dimension," where he appears as a spirit alongside the other Gold Saints, offering guidance and support to Athena in her temporal journey to save Pegasus Seiya.