Christina Sakurako Kujirase, nicknamed Chris, is a British-born individual raised in Shanghai, working as a bomb disposal and computer systems expert. Ranked among the top eight students in her 148-member class at Mihama Academy, she tutors classmates academically while balancing her role as a dormitory supervisor, overseeing chores like cooking, laundry, and cleaning. Her demeanor blends quiet shyness, approachable warmth, and formal politeness, though whispers among peers caution against inciting her hidden intensity. Despite an aversion to firearms, she sometimes carries a malfunctioning self-defense pistol—a flawed product she absentmindedly acquired.

Her appearance features short blonde hair, permanently altered after a childhood bomb experiment accident destroyed her original long locks. She favors functional attire: a school uniform paired with a hairband, tights, and a wristwatch. Chronic nearsightedness requires daytime contact lenses, with glasses reserved briefly upon waking. Physical attributes include green eyes, a youthful face, and measurements of 84-56-79 cm.

As a caretaker, she exhibits tactile affection, offering piggyback rides, cradling peers in her lap, and initiating casual touch during sleep. She shares a protective guardianship over Taiga Sengoku, occasionally embracing her chest while resting. Another peer, Tōka, earns her playful teasing as a "classic Japanese cutie" and tsundere archetype.

Her childhood fascination with homemade explosives caused the hair-destroying blast, a penchant for risky technical improvisation that lingers into adulthood through her use of unreliable gear. Across adaptations, she anchors her group as both a domestic manager and tactically trained specialist, harmonizing routine duties with combat readiness.