Serge Entolio, a half-elf spell breaker from a magically advanced realm, wields expertise in dismantling curses, erecting barriers, and sealing supernatural forces—skills vital to combating arcane threats. His golden hair and deep blue eyes frame a faint line etched across his forehead, a hereditary mark shared with his brother Hasga, while his rugged vest and torn pants echo their mirrored style. Driven by the Church’s cruel exploitation of their mother, Ela of the East—a victim of traumatic experiments—Serge orchestrates a risky gambit to secure her freedom. The plan hinges on capturing Saitohimea, a vampire sorceress, to trade for Ela’s release, necessitating the abduction of Haruka Shigure, Saitohimea’s linked classmate. Though desperate, Serge refuses to harm women, adhering to a personal code that tempers his ruthless strategy.

Calm and methodical, he counterbalances Hasga’s impulsiveness, his friendly smiles cloaking a cunning mind fixated on long-term objectives. Despite sharing his brother’s appreciation for beauty, he subordinates personal desires to their mission. After rescuing Ela, the brothers ally with Gekkou Kurenai’s student council, transitioning from adversaries to reluctant collaborators in the human world’s hidden wars.

A master of containment, Serge crafts barriers to imprison formidable entities, his initial hostility toward figures like Taito Kurogane rooted in familial loyalty rather than malice. This moral ambiguity defines him—a pragmatist willing to leverage hostages like Haruka yet capable of redemption. Their integration into the council underscores a shifting allegiance, though their past shadows their newfound role. His story remains anchored to his bond with Hasga and their relentless drive to shield their family, with no documented evolution beyond the main series’ confines.