Kōji Tajima leads Namidome Industries, a small pest control company dedicated to exterminating giant beasts infesting evacuated Ryugan Island. He transformed a failing construction firm into this venture following the island's gas leak evacuation, driven by the goal of reclaiming the territory for displaced residents. His pragmatic leadership balances the company's financial constraints against its critical mission to eliminate the mysterious creatures. Tajima operates with an accommodating style, actively integrating team suggestions to enhance operational efficiency. He maintains transparency with the frustrated local community regarding delays in their return while legally concealing the beasts' existence from public and government scrutiny to circumvent bureaucratic interference. His commitment is fueled by his theory that these creatures generate the hazardous gas causing the evacuation, intensifying his resolve to eradicate them. Persistent financial instability forces Tajima to navigate challenges like ammunition costs, equipment maintenance, and pressure from the Builders' Union restricting boat access to the island. He spearheads rebranding efforts to bolster the company's public image and secure vital community support. When corporate maneuvering by parent company Shiota Chemical pushes Namidome Industries toward collapse, Tajima authorizes high-risk strategies, including deploying leather coral as a secret weapon to thwart Shiota's hostile takeover. His crisis decisions prioritize preserving the company's autonomy and safeguarding the islanders' interests. Key relationships define his approach: he mentors Tetsurō Okino, designer of the Bullbuster robot, after Okino's mistakes jeopardize the company; collaborates closely with cost-conscious accountant Kintarō Kataoka; and coordinates with researchers like Shiota Bio's Mitsuru Inomata to study the beasts. His interactions with the islanders consistently reflect his accountability to those displaced by the creatures.