Shinji Ishida is a doctor specializing in rescuing financially collapsing hospitals. He markets a reputation built on revitalizing failing medical institutions through unconventional methods. His core therapeutic tactic involves intrusive sadomasochistic "treatments" centered on patient humiliation. These include sexual acts, voyeurism, and direct participation in patient masturbation, deliberately designed to create patient dependency. This ensures patients pay generously to continue receiving care, solving the hospital's revenue issues.

He primarily targets young female patients but also pursues a mature woman, Mrs. Kinoshita, exploiting her stress under the guise of treatment. He leverages the vulnerability of affluent patients like the neglected heiress Ms. Higashijuuju, using their emotional needs to foster financial reliance. His interactions extend to treating Tomomi Kinoshita's ankle injury, but his focus shifts to exploiting her mother's marital dissatisfaction for sexual and financial gain.

He operates with Kyoko Shirakawa, a former sex worker who poses as a nurse. She assists by providing sexual favors to male patients, aligning with his revenue-driven model. Their professional relationship includes sexual encounters, maintained as transactional. Concurrently, Honoka, the hospital owner's daughter and a nurse, develops an obsessive attraction toward him, which he largely ignores due to his focus on expanding patient exploitation.

His character remains consistent, employing ethically bankrupt methods for hospital profitability. No significant evolution, deeper background regarding motivations or history, or exploration of internal conflicts, origins, or future trajectory beyond the initial storyline is depicted.