Gaō Mikado serves as the central protagonist across the Future Card Buddyfight series and Future Card Buddyfight 100. A sixth-grade student at Aibo Academy's elementary division, he is the younger brother of the late Yota Mikado. Yota's comic "Mighty Sun Fighter" profoundly shapes Gao's identity; he adopts its persona, symbolized by his reversible sun-motif jacket and his catchphrase about eclipsing darkness with flames to brighten hearts. His family operates a dojo where he trains in Mikado-style Aiki-jujutsu under his mother Suzumi. Gao embodies unwavering optimism, a strong sense of justice, and a deep belief in friendship's power to redeem. He actively defends those in need, exemplified by protecting Kiri Hyoryu from bullies. However, he harbors a violent temper surfacing under extreme stress, leading to aggression. This duality stems from a traumatic childhood incident where his obsession with winning at martial arts caused him to injure an opponent, resulting in lasting guilt and fear of repeating such actions. Consequently, he initially shies from competitive intensity in Buddyfighting, though he occasionally struggles to control his anger, as seen in his one-turn victory against Rouga Aragami. His Buddyfighting journey ignites after summoning his first buddy, Drum Bunker Dragon, with a Buddy Rare card. Despite his novice status, he quickly demonstrates exceptional natural talent, defeating seasoned fighters like Tasuku Ryuenji. Gao forms Team Balle du Soleil with Baku Omori (deck builder) and Kuguru Uki (analyst) to compete in tournaments like the ABC Cup. His early Dragon World decks employ aggressive strategies and shield-counter spells, often leaving his center vulnerable. His core philosophy—that Buddyfighting fosters bonds—drives his efforts to befriend adversaries, including former rivals like Kyoya Gaen. In Future Card Buddyfight 100, Gao confronts the planet-consuming entity Yamigedo and its partner, Ikazuchi. This arc shatters his confidence; losing to Ikazuchi ends his 999-win streak, and witnessing Tenbu's apparent death plunges him into a depressive state where holding cards causes physical pain. He temporarily quits Buddyfighting until rediscovering his passion through peer encouragement and a celebrity guest fighter. Joining the Buddy Police, Gao and Drum seek eight Omni Lords to seal Yamigedo. Drum temporarily becomes an Omni Lord, evolving into Ultimate Neo Dragon, Drum The Future, before returning to Dragon World to lead his clan. Gao's abilities expand across seasons. He wields Future Force, unconsciously materializing cards during danger or rage, later gaining conscious control. In Triple D, after Drum's departure, Gao bonds with the newborn sun dragon Bal, mentoring him while using Sun Dragon decks. Witnessing Bal's poisoning unlocks his Dragon Force of Anger, unleashing a fiery aura that enhances his physical capabilities and evolves into "Style of Impact." During the World Buddy Cup, he combats Kyoya Gaen and the malevolent Azi Dahaka. In Future Card Buddyfight X, representing Dragon World in the World Buddy Masters tournament, Gao releases the sealed Demon Lord Dragon Batzz. Despite Batzz's destructive history, Gao befriends him, adopting Thunder Empire decks centered on the Overturn mechanic. This partnership strains Gao physically; using Impacts like Thunder X Tempest Buster risks painful Draconification or life force depletion. He later synthesizes Future Force, Dragon Force, and Draconification into Future Force DX. Post-tournament, he prevents Batzz's resealing by Saint Glory Sword Dragon, reinforcing their bond. Gao's later life includes marrying Paruko Nanana and fathering two sons, Yuga and Haru. He moves to America after Buddyfight X, referenced but unseen in Buddyfight Ace. His legacy endures through his children and the GGG Cup tournament held in his honor.