Chikage Rokuoin (鹿王院 千景, Rokuōin Chikage), bearing a surname signifying "deer" (鹿) and "royal palace" (王院) and a given name meaning "thousand" (千) and "scenery" (景), commands the Ex-Arm Countermeasure Division with the rank of police inspector. She operates within this division as assistant to section chief Soushi Shiga, strategically directing field operations. Her tactical proficiency, honed through skill in first-person shooter games, informs her law enforcement approach.

Physically, she is an adult female characterized by waist-length blonde hair, blue eyes, distinctive cheek curls, and a standard military-style uniform.

Leading her division's efforts against advanced Ex-Arms weapon systems, she oversees a team including engineer Alisa Himegami, exoskeleton specialist Kimura, and sniper Kondou.