Yoshihiko Sagami—a name blending "fragrant, virtuous, beautiful" and "boy, prince," paired with a surname evoking "phase, aspect" and "imitation"—leverages his elite military special forces background as a tactical cornerstone within a team infiltrating a quarantined zone. A seasoned strategist, his combat expertise and unflappable composure under pressure anchor missions, where he wields firearms, blades, and calculated decisions to navigate lethal environments. Partnered with Kazuki Minase, a novice agent sporting a prosthetic arm, Yoshihiko adopts a stern but protective mentorship, tempering Kazuki’s impulsiveness with battlefield pragmatism. His leadership, forged through years of special operations, positions him as the team’s second-in-command, bridging the gap between veteran commanders and frontline execution. Though his discipline occasionally sharpens toward Kazuki, it masks a deliberate focus on the younger agent’s survival and skill refinement. During high-stakes operations, Yoshihiko orchestrates team movements, blending tactical precision with adaptive maneuvers to outmaneuver threats, ensuring collective survival through relentless analysis and hardened experience.