Souma Oogami is a teenage boy with short black hair, brown eyes, and a distinctive Orochi mark etched on his forehead. A seemingly popular student at Ototachibana Academy, his social prominence parallels Chikane Himemiya’s, though their paths seldom intersect before the Orochi’s reawakening. His childhood, marked by abuse under a violent father, ends when his older brother Tsubasa kills their parent and abandons Souma to the Ogami family’s care—a trauma forging his protective nature and rigid ethical code.

As the seventh Neck of Orochi, Souma rebels against the deity’s control when Himeko Kurusugawa, his childhood friend and unreciprocated love, faces danger. Defying his fate, he commands the mecha Take-no-Yamikazuchi—a weapon meant for Orochi’s destruction—to shield Himeko and Chikane. Even as Orochi’s corruption manifests as encroaching scales on his body, he fights using martial prowess and a sword gifted by Tsubasa, enduring physical agony to protect others.

His bond with Himeko shifts from quiet longing to sacrificial loyalty. Despite confessing his feelings, he graciously accepts her choice of Chikane, prioritizing her happiness over his own. Ties to Tsubasa deepen when their biological kinship surfaces: Tsubasa, initially luring Souma to Orochi’s cause, redeems himself by severing Souma’s curse through self-sacrifice, mending their fractured brotherhood.

When Chikane temporarily hijacks Take-no-Yamikazuchi to advance her own sacrificial agenda, Souma reclaims the mecha, augmented by energy wings from Tsubasa’s robot. He joins Himeko and Chikane in the climactic clash against Orochi, pivotal to the deity’s downfall. Post-battle, Orochi’s taint purges from him, yet his memories of Himeko linger in uncertainty.

Souma’s story arcs across struggles against predestination, anchored by loyalty and agency. Adopting Kazuki Ogami’s surname, riding a motorcycle, and standing as Orochi’s sole reluctant vessel, he embodies a warrior defiant of destiny, guided by conscience over cosmic design.