Yomogi Asanaga, a first-year student at Fujiyokidai High School, saw his ordinary life shattered when Gauma, a self-proclaimed "Kaiju user," recruited him. Gauma needed pilots for the giant robot Dynazenon to fight kaiju unleashed by the Kaiju Eugenicists. Yomogi joined classmates Yume Minami, NEET Koyomi Yamanaka, and later Chise Asukagawa, specifically piloting the Dyna Soldier component of the modular robot (which also included Dyna Wing, Dyna Diver, and Dyna Striker). Months of intense training transformed the initially inexperienced Yomogi into a proficient pilot. He mastered Dynazenon's combat systems and its powerful combinations: Wing Combine for flight and energy beams, Striker Combine for fire attacks, and the ultimate Dyna Rex formation, capable of vaporizing kaiju with fire. Success required synchronized emotions from all four pilots. Beyond kaiju battles, Yomogi grappled with personal turmoil stemming from his parents' divorce and his mother's new relationship, contributing to his reserved nature. His bond with co-pilot Yume Minami deepened as they confronted their traumas—his family issues and her grief over her sister Kano's death. Shared reliance during combat fostered mutual trust and gradual emotional openness between them. A late-series revelation identified Yomogi as a Repli-Compoid, a digital human replica granting interaction with non-corporeal entities. He also possessed innate Kaiju User abilities, including "Instance Domination," which could forcibly enlarge kaiju and amplify their aggression. This dual nature as both kaiju controller and Dynazenon defender created significant internal conflict regarding his role in destruction. Yomogi's journey centered on reconciling this identity and processing his trauma. Piloting Dynazenon became a conduit for confronting his family issues and forging deep bonds, particularly with Yume. By the series' end, he achieved greater self-acceptance, solidified his team relationships, and fully embraced his responsibilities defending against kaiju threats.