Sakura Sakurakouji, a gentle yet skilled martial artist, witnesses a disturbing incident of blue flames engulfing individuals on her bus ride home. Despite her report to the authorities yielding no clues, her certainty wavers until the arrival of transfer student Rei Oogami. To her disbelief, Rei, the alleged perpetrator, appears as a charming and popular peer. Sakura soon uncovers Rei's identity as a Code Breaker, a clandestine agent of justice with formidable powers. Shocked by his vigilante methods, Sakura resolves to guide Rei towards a path of redemption, standing by him to prevent further harm.