Toru Acura, orphaned young, trained as a saboteur in the hidden Acura Village, mastering espionage, combat, and infiltration. Childhood visits from Jasmine Hulo, a merchant's daughter who shared outside world stories, forged a deep bond. Jasmine discouraged his eagerness for the ongoing war, urging alternative ways to leave his mark. Her death in a bandit attack solidified his belief that war was his only path to "proof of living." The war's end before his deployment left him directionless. The subsequent destruction of Acura Village forced him to flee with his adopted sister, Akari Acura.

Post-war, Toru became lethargic and purposeless, refusing work while sleeping and eating, his mantra "I'll lose if I work" reflecting his disillusionment. This changed encountering Chaika Trabant, a coffin-carrying sorceress, during foraging. After aiding her against a man-eating unicorn, he accepted her mission to collect the scattered remains of her father, Emperor Gaz. The quest reignited his purpose, shifting his focus from seeking war to dedicating himself entirely to Chaika's goals. His loyalty remained unwavering even after learning her actions could reignite continental conflict, stating he was "okay with war" supporting her objectives.

Toru possesses exceptional saboteur-honed combat abilities. His physical conditioning enables acrobatic maneuvers, stealth reconnaissance, and strategic battle planning. He wields dual comblades, short swords magically connected to his hands via crests, functioning as body extensions. Triggers on the blades project them via retractable wires. He also employs throwing knives for ranged combat. His signature technique, Iron Blood Transformation, optimizes physiological systems through intense mental focus. This state enhances strength, reflexes, and combat prowess but drains significant energy, requiring substantial food intake afterward. It increases toxin susceptibility by accelerating respiration. During activation, his hair turns red and crimson streaks appear across his face.

Toru's relationship with Chaika evolves from client-bodyguard to deep mutual respect and unspoken romantic feelings. He views her as his savior for restoring purpose, prioritizing her safety above all else, refusing offers to defect despite greater combat opportunities. His greatest fear is her abandoning him, though she reassures him otherwise. With non-blood sister Akari, Toru shares a complex bond. Akari is obsessively devoted, often making inappropriate remarks he ignores or deflects. Despite this, they trust each other implicitly in combat. Frederika, a shapeshifting dragoon joining their group, develops a rivalry after Toru spares her life, sympathizing with her lost purpose. She repeatedly challenges him to duels he postpones until after Chaika's mission. He eventually forms a pact with her, becoming a Dragoon Cavalier and gaining enhanced healing.

Across his journey, Toru matures from a disillusioned warrior into a strategic leader valuing protection over conflict. He consistently prioritizes others' needs, encouraging Frederika to find new purpose and choosing to serve Chaika Trabant because she "needed him more" than others. His development culminates in embracing a role beyond saboteurhood, symbolizing a complete transformation in identity and commitment.