Haniwa serves as the Minister of Defense within the narrative, occupying a key position in the organizational structure aligned with Kuroshio's operations. The character's involvement stems directly from the central conflict involving the Phantom Ship's attacks and Kuroshio's subsequent activities. As Minister, Haniwa oversees defense coordination efforts against these perceived threats, actively participating in strategic discussions and decision-making processes concerning the response to the Phantom Ship's actions. Haniwa operates within the framework of institutional authority figures connected to Kuroshio's schemes.