Goro Watari is the protagonist of Inazuman, a young man who discovers he is a powerful psychic mutant. At the start of his journey, he is a university student and a star of his college soccer club, though his past holds significant sadness. He lost his mother when he was a child and also endured the painful experience of having his childhood girlfriend, Teresa, taken away by an American soldier during the post-war occupation of Japan.

In terms of personality, Goro is characterized as a morally upright, friendly, and courageous individual. Unlike the more arrogant and cocky protagonist of the original manga, Goro is a genuine and caring hero. He is notably kind to children, showing great concern for the younger members of the Youth League and readily stepping in to help any child in distress. He is also a clever and resourceful fighter, employing cunning strategies and disguising his own injuries to lure out enemies when direct confrontation is not the best option. His fighting spirit is often vocalized with the distinctive kiai cry of "Chest!", a shout originating from the Japanese island of Kyūshū, which is his homeland.

Goro's primary motivation is to protect humanity from the threats posed by other mutants. He is drawn into this conflict when he encounters soldiers from the Neo-Human Empire Phantom Army attacking the Youth League, a group of similarly gifted psychic youngsters. After being rescued, his latent powers are awakened, and he learns of the secret war between factions of the human race. Despite the trauma of his past, Goro accepts his destiny as a warrior, fighting to thwart Emperor Banba's ambitions and later the Despar Army, all while shielding ordinary people from these superhuman threats.

His role in the story is that of the central hero and a key member of the Youth League. He allies himself closely with this group, who provide him with support and operate from a secret base. He shares a telepathic link with Raijingo, the Youth League's sentient flying car, which resembles a red vehicle with a mouth-like grill and can assist him in combat by firing missiles.

Goro's character undergoes a clear development through his transformation abilities, which function as a physical representation of his growth. To access his full power, he must go through a two-stage metamorphosis. First, by shouting "Gōriki Shōrai," he transforms into Sanagiman, an armored, brown, larva-like being with a power meter on his belt. This form is able to absorb the kinetic energy from any enemy attack. Once Sanagiman has gathered sufficient energy, he shouts "Chōriki Shōrai," causing his outer shell to burst apart and revealing his true hero form, Inazuman. This final form is a sleek, blue, moth-like humanoid with large, colorful oval eyes, lightning-bolt shaped antennae, and a yellow scarf. He gains an upgraded form known as Inazuman Flash in the sequel series to face new, more powerful adversaries.

As his name suggests, Goro's most notable abilities in his Inazuman form are based on electricity and lightning, which he uses to augment his physical attacks. He is a formidable hand-to-hand combatant, fighting with a style that incorporates punches and kicks. His yellow scarf is a versatile tool that can be transformed into various weapons, such as a chain or a whip. One of his most extraordinary powers is known as the Reverse or Reverse Chest, a kind of world-healing wave that can reverse damage, restore destroyed objects, or even reflect an enemy's attack back at them. He also demonstrates powerful psionic abilities including telepathy, telekinesis, and teleportation. In the face of overwhelming danger, Goro can even create a device called Zeber from parts of his own body, including his antenna and parts of his belt, which acts as a super-amplifier to multiply his psychic powers to even greater heights.