Taiju Ōki emerges as a central character, deeply entwined with Senku Ishigami and Yuzuriha Ogawa since childhood. His early years involved collaborative scientific ventures with Senku, such as launching a rocket laden with stuffed toys into space, and aiding Senku’s father, Byakuya Ishigami, in pre-mission preparations for space exploration. A decisive moment arose as he resolved to confess his feelings for Yuzuriha, interrupted by a cataclysmic global petrification event that transmuted humanity into stone statues for millennia. Through unwavering resolve to reunite with Yuzuriha, Taiju sustained consciousness during this stasis—a rare achievement. Revived on October 5, 5738, he rejoined Senku and played a crucial role in refining the depetrification formula. His formidable physical prowess became indispensable in resource gathering and defense, though his limited grasp of scientific theory sparked comedic mishaps. Despite this, he exhibited practical ingenuity, proposing grape fermentation for alcohol production and applying agricultural science to farming. His pacifist principles remained unshaken, refusing violence even under threat, underscoring his ethical steadfastness. Driven by loyalty to Senku and Yuzuriha, Taiju spearheaded covert intelligence operations within the Tsukasa Empire alongside Yuzuriha, balancing espionage with maintaining their facade. As leader of the Kingdom of Science’s Farming Division, he championed agricultural progress through endurance and collective effort. Transitioning from steadfast ally to tactical operative, he engaged in strategic deceptions during missions and contributed to monumental projects like the moon-landing initiative. His bond with Yuzuriha anchored his personal growth, evolving through shared trials into a partnership solidified by marriage after the lunar mission’s success. This union marked their transition from hesitant adolescents to committed collaborators in both private and societal pursuits. Taiju’s resilience deflected assaults from adversaries like Tsukasa Shishio, while his mental fortitude endured millennia of petrification and high-pressure scenarios. Though initially struggling with scientific concepts, he gradually retained and applied such knowledge, reflecting incremental intellectual growth. His blunt candor and occasional naivety occasionally required guidance from strategically minded allies. Balancing roles as guardian, laborer, and emotional pillar, Taiju’s efforts in rebuilding civilization highlighted collaborative perseverance and the integration of diverse expertise. His arc concluded by epitomizing unwavering loyalty, enduring love, and humanity’s capacity for renewal amidst existential trials.