Kyoka Tsujigai is the Supervisor of Sanctuary, a special ward for latent criminals under the Ministry of Economy, Trade and Industry's Environment Bureau. She appears to be in her 40s, of average height and slender build, with light brown eyes and mid-length gray hair styled into a flip with side bangs. Her typical attire includes a cinched white jacket featuring gray piping, a red blouse, black pants, and earrings. A government-credentialed scientist and therapist, Tsujigai developed an experimental rehabilitation program at Sanctuary. She created a specialized drug with researcher Ataru Takeda, inducing group-think among inmates. Combined with hypnotherapy, this grants her near-total control over the facility's latent criminals. Despite her outwardly articulate and pleasant demeanor, she holds deeply dehumanizing views toward the inmates, considering them subhuman and expendable for her objectives. Her methods involve forcing inmates to handle highly radioactive nuclear waste without protective equipment, justified as necessary for the "greater good." Sanctuary is situated above a former dumping ground for nuclear waste generated by the Sibyl System. Tsujigai operates under the oversight of government official Akira Karasuma, who enables her experiments while shielding them from scrutiny. Her chief security officer, the latent criminal Rodion Matsuki, shares her disdain for other inmates but later expresses remorse before committing suicide after failing to convert Inspector Nobuchika Ginoza. Tsujigai's own crime coefficient measures 421, classifying her as a latent criminal. Her experiments unravel when Inspector Mika Shimotsuki and Enforcer Ginoza investigate Sanctuary following the escape of a traumatized therapist. They expose her exploitation of inmates for radioactive labor and suppression of dissent through drugs. Shimotsuki records Tsujigai admitting her knowledge of the radiation risks and broadcasts this to the inmates, inciting a riot. During the chaos, Shimotsuki executes Tsujigai with a Dominator. Her surname "Tsujigai" combines "street/crossroad" (辻) and "domesticate/raise" (飼), while her given name "Kyoka" uses characters for "barbarian" (羌) and "fragrance" (香).