Big Fire is the enigmatic and supreme leader of the terrorist organization that shares his name. He is a figure of immense mystery, rarely seen and never fully explained, serving as the ultimate authority and the symbolic heart of the group's ambitions. Throughout the narrative, his presence is felt as a distant, almost mythic force whose will is carried out by his subordinates, particularly the Magnificent Ten, the most powerful of his agents.

His background is deliberately obscure. He is portrayed as a boy with silver hair, appearing only in brief glimpses during the latter part of the story. This youthful appearance contrasts starkly with his position as the head of a global conspiracy, adding to his inscrutable nature. His origins are a subject of speculation, with some interpretations suggesting he may be a figure who became jaded with humanity, seeking to purify it, which would inform his role as the leader of a destructive organization.

Big Fire's personality is impossible to define, as he has no dialogue or significant interaction with other characters. He is less a character with defined traits and more of a concept or a presence. This lack of definition makes him the ultimate ghost, a distant emperor whose intentions are unknowable. All actions taken by the Big Fire organization are theoretically carried out in service of his will, but what that will actually entails remains a mystery, leaving his subordinates and enemies alike to guess at his true goals.

His primary role in the story is as the figurehead of the opposing force to the International Police Organization. While other villains like Genya drive the immediate plot and the strategist Koumei orchestrates specific operations, Big Fire represents the ultimate source of their authority and the final goal of their global conquest. He is the hidden hand, the emperor on the throne, while others fight his war. His very existence as a mysterious, unquestioned leader serves to unify the often-conflicting agendas of the powerful members of his organization, as all of them, in theory, answer to him.

Key relationships are defined entirely by the service others provide to him. The Magnificent Ten, a group of ten powerful superhumans, are his direct subordinates and serve as his primary enforcers. The strategist Koumei frequently appeals to Big Fire's authority to justify his own complex and often costly plans, and no member of the Ten dares to defy a direct order or a decision made in his name. Genya, another major antagonist driven by personal revenge, also operates within the framework of Big Fire, though his personal agenda often puts him at odds with the organization's other leaders. The dynamic is one of absolute, unquestioning loyalty, or at least the appearance of it, with Big Fire as the silent, immovable figure at the top.

There is no character development for Big Fire himself, as he remains a static, distant figure. His mystery is his defining feature, and it is never resolved. The narrative does not humanize him or provide a backstory that would explain his motives. He exists as a final, unanswered question, a dark god whose reasons for seeking world domination are never made clear. The focus remains on how other characters react to and are driven by their perception of his will.

Regarding notable abilities, Big Fire is credited with having enormous power, though the exact nature and extent of these abilities are never demonstrated. He is suspected to be far more powerful than any of his subordinates, including the already superhuman members of the Magnificent Ten. However, as he never engages in combat or displays any overt power, his capabilities remain entirely within the realm of speculation, reinforcing his role as an off-screen, untouchable final authority.