TV-Series
Description
Keiji is the main protagonist of the series, a lone rooster who presents himself as a self-described migratory bird. His past is marked by tragedy, as he witnessed his younger sister Sara being killed and devoured by a powerful mutant demon known as the White Demon. This event serves as the central motivation for his journey, driving him to wander across Japan with the ultimate goal of tracking down and destroying this specific demon to avenge his sister.

In terms of personality, Keiji embodies the archetype of a grumpy and stoic wandering warrior. He carries himself with a serious demeanor and treats every situation, no matter how absurd, with the utmost gravity. He adheres to a strict personal code of conduct regarding respect and appreciation. While he generally despises children or young individuals he deems disrespectful or annoying, he has shown a softer side for certain youngsters, most notably a small chick named Piyoko. Despite his tough exterior, he has a noted fondness for hens and enjoys eating specific foods like sea urchins and stinkbugs. His internal monologue often reflects a hard-boiled, noir-like narrative, contrasting his serious thoughts with the mundane reality of being a bird.

His role in the story is that of a wandering hero who confronts giant mutant demons, called kijyu, that threaten human settlements. He refuses to stay in any one place longer than necessary, driven by his singular quest for revenge, though he inevitably becomes a protector to the people and creatures he meets along the way. Keiji is the central figure around whom other characters gather. His primary relationship is with Piyoko, a young chick who decides to follow him after he saves her guardian. Despite his reluctance, he eventually allows her to accompany him, and she becomes a constant companion, even believing she will marry him when she is older. He also shares a complicated history with Elizabeth, a hen he had a brief affair with after saving her family. He abandoned her shortly after, leading her to initially resent him, though she later joins his cause.

Throughout his journey, Keiji shows subtle development in his relationships. While he starts as a complete loner, he gradually and reluctantly accepts the companionship of Piyoko and Elizabeth, forming a ragtag group despite his refusal to openly acknowledge having teammates. His cold demeanor is shown to be a front, occasionally cracking to reveal a character who is capable of appreciation and forming attachments, even as his primary focus on revenge remains unchanged.

Keiji possesses several notable abilities that allow him to fight against monsters many times his size. His most iconic power is his fearsome battle cry, Kokekokko, which is so powerful it can generate resonance and explosive force to destroy enemies. He also has exceptional aim, being able to throw items with great precision using his beak. Physically, he is incredibly strong and agile, using his talons and beak in combat with a ferocity reminiscent of his theropod dinosaur ancestors, effectively making him as deadly as a raptor. He can also fire energy-like projectiles from his beak. He is sometimes depicted using unconventional combat tactics, such as throwing an iron pillar that explodes on impact.
Cast