Zihan Yang serves as a Chinese operative in the K321 Unit, an interplanetary military force of human recruits designated Yakitori. She exhibits unshakeable calm under duress, functioning as the team's strategist. Her analytical prowess and steady composure in combat establish her as the primary tactical planner during missions, where she coordinates squad maneuvers and crafts intricate battle plans.

Within the K321 Unit, Zihan routinely offsets Akira Ihotsu's impulsive tendencies through methodical reasoning. Her duties encompass real-time threat evaluation and response formulation during perilous operations—including enemy infiltrations and armored counterattacks—entailing vulnerability identification in hostile emplacements and live-fire direction of team movements.

Pre-enlistment records remain unspecified. In unit dynamics, she fortifies the group's emergent cohesion during combat, where synchronized tactics dictate survival. Her strategic insights critically enable the K321 Unit's navigation of hostile terrain and resolution of complex tactical hurdles.