Iwakura is a newspaper reporter who plays a pivotal role as the first human to encounter the protagonist, Mars. His actions occur at the very beginning of the narrative, establishing him as a key figure whose sense of duty sets the story's central conflict in motion. As a member of a newspaper organization identified as the Asayomi, Iwakura is sent on an assignment to cover the dramatic formation of a new volcanic island, named Heisei Island, in the sea near Japan. Upon arriving at this newly formed and uninhabited landmass, he makes the extraordinary discovery of a young, naked boy who appears to have been in a state of suspended animation. Iwakura immediately takes charge of the situation, calling for help to rescue the disoriented boy, who has no memory of his past or identity.

Iwakura’s role quickly evolves from that of a simple reporter to a guardian and investigator. After the boy, who later learns his name is Mars, is taken to a Tokyo hospital, Iwakura continues to involve himself in the mystery. Unlike others who might step away after filing their initial report, Iwakura is driven by a strong sense of responsibility. He dedicates himself to uncovering the secrets behind Mars’s origins, understanding that the boy is connected to something far greater than an ordinary amnesiac. He returns to the newly formed island and the facility where Mars was found. Using his wits and determination, Iwakura manages to decipher a portion of the complex information stored within an alien computer on the island, gradually piecing together the truth about Mars, the giant robot Gaia, and the potential threat to Earth.

His primary motivation is to protect both Mars and humanity from an unknown but clearly imminent danger. He is not a fighter or a scientist, but a journalist who believes that uncovering the truth is the first step toward preventing a catastrophe. As he learns more about Mars’s intended purpose as an agent of destruction, his goal becomes to help the boy defy his original programming. He works alongside other supportive adult figures, such as Doctor Yokoyama, who provides Mars with a place to stay, to build a support network around the confused protagonist.

Iwakura’s relationship with Mars is that of a rescuer and a trusted, fatherly ally. It is built on the foundation of Iwakura finding Mars at his most vulnerable moment and choosing to help him without hesitation. This initial trust allows Iwakura to become one of the few people Mars can rely on as he struggles to understand his identity and mission. The character’s development is ultimately cut short by a tragic act of self-sacrifice. After extracting a critical piece of information from the alien computer, Iwakura pays the ultimate price for his pursuit of the truth. Before he dies, he ensures that the decoded information reaches Mars, giving him the knowledge he needs to continue the fight. His death serves as a powerful catalyst, reinforcing the high stakes of the conflict and the tragic consequences of the alien conspiracy.

In terms of abilities, Iwakura possesses no superhuman powers or combat skills. His most notable assets are his professional investigative skills, his sharp intuition, and his moral courage. As a seasoned reporter, he is trained to ask the right questions, follow leads, and piece together disparate clues into a coherent narrative. It is this intellectual tenacity, rather than any physical strength, that allows him to successfully breach the alien technology and uncover its secrets, making him an unsung hero whose contributions are vital to the early stages of the story.