Garoben

Beneath her human cover, Garoben is a red-skinned female creature with dark, spiky hair and a pale purple mark on her forehead. Sharp spikes push out from her shoulders and along her back, and one of her hands can reshape itself into an axe, a weapon she threatens to bring down on Ami's neck.

What sets Garoben apart is her combat method: instead of striking outright, she interrogates her opponent and only lashes out when they answer wrongly, turning the battle into a twisted exam. She is coldly manipulative in her instructor guise and grows visibly enraged when a victim slips free of her control.

Jadeite is keen to weaponize computers against people, draining the energy they pour into chasing academic success, so he sends Garoben to pose as a teacher at the Crystal Seminar cram school. She launches a computer course and pushes a so-called Crystal Disk, a 3.5-inch floppy she claims holds revolutionary software that makes any user a genius over time. The disk actually runs brainwashing code that saps energy and reduces students to obedient zombies. Usagi and Luna grow suspicious of Ami Mizuno after she loses her copy of the disk at the Crown Game Center, and Usagi investigates the school disguised as a doctor. Realizing the students are being conditioned, she confronts Ami and becomes Sailor Moon, only for Garoben to seize Ami as a hostage and drop her human form. In the fight, Garoben quizzes Sailor Moon and, when she refuses a math problem, flings test papers that sharpen into knives; the heroine dodges but gets boxed in by the brainwashed students. As Ami's energy is siphoned before the glowing computer, she resists, and the furious monster turns her left arm into an axe to kill her. Ami evades the swing, transforms into Sailor Mercury, and unleashes Bubble Spray, which frees the entranced students and blankets the room in cold mist, giving Sailor Moon the opening to end the shivering monster with Moon Tiara Action.