Chachamaru Karakuri holds seat number 10 in Japanese alphabetical order within Mahora Academy's Class 2/3-A. She is an android forged from technology and magic, engineered primarily by classmate Satomi Hakase (with potential contributions from Chao Lingshen) to act as partner and protector for the immortal vampiress Evangeline A.K. McDowell. Her primary teenage body stands 174 cm tall, weighs 76 kg, and features light green hair, blue eyes, and distinctive mechanical ears. A hybrid power system requires daily winding; a specialized key inserted into the back of her head by a magic user infuses magical energy, generating sensations comparable to human pleasure. Initially presented as emotionless and obedient, Chachamaru displays subtle signs of developing humanity. She dedicates significant free time to assisting others, rescuing stray animals (especially cats), and participating in the Go Club and Tea Ceremony Club alongside Evangeline. Her evolving emotions manifest physiologically: internal gears accelerate during moments mimicking human adrenaline or affection, and lens-cleaning fluid secretes from her eyes when distressed, simulating tears. A pivotal moment occurs when Negi Springfield refuses to harm her during a confrontation, triggering romantic feelings that contradict her original programming. This causes significant internal conflict, nearly resulting in cognitive failure when her feelings are publicly acknowledged. Chachamaru undergoes multiple physical upgrades and model changes engineered by Hakase: - **Teenage Body v.1**: Original form with visible mechanical joints and pronounced ears. - **Young Body v.1**: Shorter, more human-like appearance with concealed joints, used temporarily during primary body upgrades. - **10-Year-Old Body v.1**: Disguise facilitated by Evangeline's illusion magic during the Magical World arc. - **Teenage Body v.2**: Enhanced form with near-human synthetic skin, extended operational capacity (24 hours between windings), and combat-focused arm transformations into blades or projectile weapons, though these drain energy rapidly. Her combat capabilities include superhuman strength, agility, and durability; magic-powered thrusters enabling 15-minute flight; optical lasers; homing missiles; rocket fists; electrical binding wires; and a "Bind Canceller" device to disrupt magical traps. Later upgrades grant martial arts proficiency comparable to elite fighters, including techniques like "Shundō" (Instant Movement). As Negi’s Pactio partner, her artifact—Type-2130 Chao Bao Zi Satellite Support System: Al-Iskandariya (colloquially "Catwing")—enables orbital laser strikes tunable from destructive to non-lethal settings (e.g., removing clothing). This Pactio also confirms her possession of a soul, resolving a previous insecurity. Her narrative arc involves shifting loyalties and self-discovery. Initially opposing Negi alongside Evangeline or under Chao Lingshen’s programming during the Mahora Festival, she later allies with him after Chao declares her a "free unit." Key relationships include unwavering devotion to Evangeline; a complex mentorship with creator Hakase, who obsessively monitors her emotional growth; and an unexpected friendship with reclusive hacker Chisame Hasegawa, whom she supports through shared uncertainties about magic and personal connections. By the series’ epilogue, she serves as a caretaker for Ayaka Yukihiro centuries later during the events of "UQ Holder!".