Kôtarô Taiga holds the dual leadership roles of president for the Space Development Corporation and chief of the Gutsy Geoid Guard, later known as the Gutsy Galaxy Guard (GGG). As GGG chief, he commands missions and personally authorizes critical operations like Final Fusion, Symmetrical Docking, and the deployment of experimental weaponry such as the Goldion Hammer, Goldion Crusher, and Projectile X. Taiga reports to overseeing bodies, including the Japanese Diet and later the United Nations, advocating for GGG's budget and purpose. His authorization, signified by the Gold Key container, represents the Japanese Prime Minister for Earth missions and the UN Secretary General for space operations.

Previously, Taiga operated under the codename Gold Tiger, leading the covert group ID5. After the television series events, he temporarily stepped down from GGG to focus on corporate duties at the Space Development Corporation and research potential risks linked to "The Power." He remained a staunch GGG advocate, notably defending them before the United Nations when permission to pursue the Sol Masters into space was denied. When GGG launched despite UN orders, resulting in GaoFighGar's Final Fusion program being disabled, Taiga intervened. He revealed a flash drive containing a backup of the program concealed within his golf club, enabling GGG to continue. He subsequently rejoined the exiled GGG members to lead their campaign in the trinary star system.

Taiga possesses a loud, energetic, and proud personality. He is married with two daughters. His hobby is golf, and he skillfully wields customized clubs like the "Titan Head Driver" and later the "Taiga Wood," which double as combat weapons—a practice originating from his ID5 service where a golf club also served as his primary weapon.