His Excellency appears as a canine-like alien commanding the Sealing Faction, directly opposing Sensei's Pacifist Faction. He enforces an authoritarian doctrine, demanding forceful planetary subjugation to prevent civilizations from evolving into future galactic dangers. This strategy stands in stark opposition to Sensei's principles of non-interference and voluntary cooperation.

His true identity emerges as Generalissimo, a high-ranking Nebula military figure. He orchestrated the destruction of Sirius, convinced its civilization posed an imminent threat to galactic stability. This act directly triggered Souya Kuroi's displacement and quest for vengeance.

Generalissimo's past reveals a longstanding ideological clash with Sensei. He views Sensei's chronic heroism and pacifism as dangerously naive, fundamentally incapable of securing lasting peace. Their opposing philosophies ignite the series' interstellar conflict, with Generalissimo championing preemptive annihilation as a necessary, pragmatic safeguard for the wider galaxy.

During the climax, he confronts Souya and Sensei directly. Despite deploying formidable power and strategic prowess, he is defeated. This loss compels him to witness the efficacy of Sensei's methods firsthand, particularly the power of empathy and reconciliation demonstrated by Ginko towards the Dragon. Following defeat, he acknowledges the validity of Sensei's approach and ceases hostilities, implicitly conceding the failure of his rigid, authoritarian ideology.

His arc concludes without explicit depiction of activities post-defeat. The resolution implies his acceptance of the new paradigm established by Sensei and Souya, marking an end to his campaign of enforced subjugation.