Dogora

A shrewd and methodical detective who threads together the global diamond disappearances with Munakata's laboratory discoveries. He pieces together clues from Yokohama to international agencies and maintains resolve as the case escalates from thefts to a creature-based mystery. His calm, analytical approach anchors the story amid chaotic events.

A crystallographer whose theoretical work suggests that space cells mutated by satellite radiation could manifest as Dogora. He leads the scientific investigation, forming the bridge between laboratory findings and real-world threat. His curiosity and confidence drive pivotal moments in understanding and confronting the organism.

Munakata's lab assistant, who coordinates information flow and conveys crucial updates to Komai. Her role ties laboratory work to practical action and helps connect the human witnesses to the scientific explanation. She acts as a communicative link between science and law enforcement.

Masayo's brother who works at the Electric Wave Laboratory and contributes technical insight. He aids the investigation with his understanding of the lab's equipment and the interplay between electricity, radiation, and the Space Planning Committee's findings. His presence underscores the collaboration between family, science, and security.

A self-proclaimed diamond broker who is later revealed to be an investigator for the World Diamond Insurance Association. He provides a civilian front to the diamond case, but his true role as an undercover investigator adds layers to the plot. He escapes danger and contributes crucial information to identify the thief.

The ruthless leader of the criminals who attempt to steal real diamonds. His schemes propel the plot and bring the criminal underworld into contact with the science-based defense against Dogora. His greed and bold tactics ultimately collide with the planet's defensive response.

A witness aboard the diamond truck whose presence illuminates the heist sequence and the criminals' increasing desperation. The passenger's experience helps highlight the high-stakes danger surrounding the thefts and the global impact of the diamond trade.