Daiichi was a diligent and responsible young man, despite his rough "no-nonsense" exterior. He devotedly cared for his three younger siblings: Yoshi, Futaba, and Santa. This responsibility fell to him after their mother passed away early on, and their father vanished without explanation three years prior. Their paternal uncle compensated for his brother's absence by renting a house for the four siblings and covering all expenses. Daiichi contributed by working as a mail and newspaper delivery boy, and assisting in his uncle's landscaping business during his days off. Choosing to live independently from his uncle with his siblings, he hoped it would provide a home for their father should he ever return.
When Daiichi and the other main characters first encountered Zearth, he was the first to express doubts and attempted to leave the "game" before the group uncovered the truth about their involvement. His chair was not a conventional one but merely a floating cushion, leading to some playful teasing from the other kids regarding his lack of imagination. During the fourth battle, Daiichi insisted on waiting until the citizens had enough time to evacuate, a practice that subsequent pilots adopted.
As the battle commenced, Daiichi’s determination to safeguard his family granted him the strength to subdue Drum long enough to carry it to the bay, ensuring no further casualties among civilians. His final request to the group was for Ushiro to cease abusing Kana and take care of her, and for Dung Beetle to discreetly dispose of his body so his family wouldn’t mourn him. His story concludes with his siblings visiting the amusement park Daiichi had protected from Drum using the tickets he had secured for them. The battle resulted in 4,384 casualties, all caused by the enemy.
