TV-Series
Description
Hakurō serves as the chief instructor of Tempest's military and an executive under Rimuru Tempest. Originally an elderly Ogre, he possessed silver hair, ivory horns, and a subtle silver skin tint, typically wearing traditional robes with a scarf covering his mouth. Rimuru's naming transformed him into a Kijin, granting a middle-aged appearance with sharper features, a silver goatee, and refined attire including a white overcoat and scarf.

His background identifies him as the grandson of master swordsman Byakuya Araki and the former martial instructor for the Ogre royal guard. He notably trained King Gazel Dwargo 300 years prior. Despite the typical Ogre lifespan of 100 years, Hakurō lived over 300 years before Rimuru's naming extended his life through evolution.

Personality-wise, Hakurō maintains calmness and analytically assesses combat situations, recognizing skills and magic with minimal exposure. He strongly dislikes being called "old man," often threatening offenders with increased training or death. Allies trust his wisdom as a "Sword Savant." Discovering his daughter Momiji made him notably overprotective; he encourages her pursuit of Benimaru and expresses irritation at Benimaru's hesitation regarding marriage.

In combat and instruction, he emphasizes teaching sword arts over reliance on innate skills, believing monsters overly depend on the latter. He mentors warriors like Gobta, identifying latent talent despite Gobta's comedic demeanor, employing notoriously strict training methods.

His role expands with Tempest's growth across all media. He participates in strategic discussions, such as countering Falmuth's crystal barrier in the light novel (adapted as dialogue in the anime). *The Slime Diaries* highlights his daily interactions: overseeing trainees, engaging in town activities, and displaying paternal concern for Momiji. This spin-off contrasts his stern demeanor with lighthearted moments, such as comically threatening those who reference his age.

His development includes transitioning from a secluded Ogre instructor to an integral leader in Tempest, balancing combat duties with familial relationships and administrative responsibilities.