Kazuki Minase is a Diver tasked with traversing hazardous zones overrun by Malignant Matter. Though newer to the role than his peers, he offsets inexperience with fierce determination and relentless enthusiasm—traits that occasionally veer into recklessness. A skilled electronics specialist, he provides critical tactical support to his partner, Sagami, during operations. His prosthetic right arm, forged from artificial life-form technology after Malignant Matter devoured his original limb during a mission, serves as both a tool and a conduit. The arm intermittently unlocks fragmented memories of Aiko Tachibana, tethering their fates through these visions. Kazuki fled a life of luxury and familial tension, his privileged upbringing shadowed by accusations of entitlement. Within the team, he clashes with a sharp-edged rivalry against a female comrade and harbors distrust toward figures like Dr. Yura and Haruka Shiraishi. His growing affection for Aiko drives him to shield her at all costs, even when it jeopardizes his own safety. This loyalty defines his actions, particularly as the group ventures toward the enigmatic Primary Point. The loss of his arm and subsequent encounters with Malignant Matter propel his evolution, merging his personal journey with the mission to halt the Burst. Interactions with teammates expose layers of resilience and vulnerability, shaped by his complex history and the psychological toll of his prosthetic. His arc weaves threads of identity, sacrifice, and adaptation as he navigates the physical and emotional demands of his dual existence as both survivor and protector.