Born November 18 as the second son of Professor Kentaro Gou and Mitsuyo Gou, Daijirou Gou transformed from a playful child into a cynic after his father's unexplained disappearance. Concerned, his mother sent him to the countryside for intensive martial arts training. There, he mastered multiple hand-to-hand combat styles and meditation techniques, favoring the Bō staff as his weapon.

Reuniting with brothers Kenichi and Hiyoshi, he joined the Voltes Team as defense tactician. He piloted the Volt Panzer, forming Voltes V's chest and body, wearing a dark green and white uniform with a yellow "V" insignia. His role focused on formulating protective strategies against the Boazanian invaders.

Daijirou blended tactical pragmatism with underlying compassion, displaying consistent care for animals like adopting a stray puppy during a mission. A pivotal revelation occurred when he and his brothers discovered their half-Boazanian heritage through their father, the exiled Prince Gohl. This forced Daijirou to reconcile his human identity with his alien ancestry amidst conflict with the Boazanian Empire and its oppressive caste system targeting hornless citizens like their father.

The death of his mother Mitsuyo, who sacrificed herself saving Voltes V in an early battle, profoundly impacted him. This loss, coupled with the search for their missing father, intensified his resolve. His martial prowess remained vital to the team, engaging directly against formidable foes like Beast Knights enhanced with Maxingal Alloy. Relationships within the team, particularly his dynamic with the hot-tempered Ippei Mine, involved clashes that evolved into mutual respect through shared missions.

Following Boazania's liberation and the dismantling of its caste system, Daijirou continued protecting Earth with the Voltes Team, upholding the values of justice instilled by his parents.