Mamoru Sakazaki held the position of homeroom teacher at Hijirigasaka Academy, projecting an image of benevolence that earned respect from students and faculty alike. Behind this composed façade lay a history of calculated manipulation and predatory actions, including documented sexual misconduct toward female students—a truth later unearthed through school nurse Chisato Hasegawa’s fragmented memories. Before the academy’s central conflicts unfolded, the original Mamoru was slain by Ornis, a celestial entity that usurped his identity to infiltrate the institution.

The impostor meticulously replicated Mamoru’s appearance—dark hair, piercing gray eyes, and professional attire—while covertly furthering the agendas of his heavenly faction. Posing as the educator, he orchestrated confrontations by manipulating students into magical puppetry, weaponizing their energies to channel destructive assaults. His fixation on Chisato spiraled into violent obsession, driving him to target perceived rival Basara Tojo for elimination. During a climactic clash, the impersonator’s celestial origins and luminous powers were laid bare. Cornered after a failed hostage gambit against Basara, he met his end through Chisato’s decisive intervention, his form dissolving under her strike. The convergence of the real Mamoru’s murder and the impostor’s machinations crystallized his dual legacy: a veneer of paternal concern masking ruthless celestial ambition. His arc culminated in the exposure of both his demise and the divine deception that shaped the academy’s hidden turmoil.