Kana Morishita serves as a Japanese government spy, a "chouhouin" (諜報員), within a state organization. She possesses green hair, green eyes, and stands 1.55 meters tall, with recorded measurements of 105-58-95.

Morishita works with fellow agents Yuuki Miyagawa and Reiko Carrere Yukiko. Their joint mission focuses on gathering evidence against a pharmaceutical company suspected of manufacturing illegal drugs.

An undisclosed tip-off alerts the company to the espionage. Consequently, Morishita and her colleagues fall captive to the company's researchers. These researchers use them as test subjects for experimental medicines under development, justifying the acts as scientific experimentation.

During imprisonment, the agents endure invasive experimental surgeries tied to the new drugs. These procedures inflict severe physical and psychological trauma, nearly destroying them. The core narrative centers on their struggle for survival and potential escape from the facility.