Prison Doctor

Biodata

Power Progression

Containment

• Requirement: He must regularly receive a patient to treat; otherwise, he goes berserk 6.
• Purpose of the requirement: The patients provide an outlet for his accumulated madness. The Director identifies a missed weekly opportunity to vent as the cause of his rampage 301.
• Safe does not mean harmless: His S-safe designation generally means that he does not attack unless provoked, not that he is incapable of violence 10.
• Assistance through negotiation: His documented terms require the beneficiary to accept treatment and praise his medical skills. He insists that he honors agreements 6 86.
• Limits of physical containment: The Doctor acknowledges that the facility cannot reliably stop him and Chainsaw Man from forcing their way into the Corrupted Creator’s room 86.

Background / History

Human Medical Career

The Prison Doctor originally worked as a human physician during the Middle Ages. He wore a wax-soaked canvas shirt and a beaked mask stuffed with cotton, carrying a wooden stick to lift patients’ clothing and bedding and direct their self-care. His medical knowledge was limited, but he remembered approaching the work with passion and responsibility 6 685.

His memories include struggling to breathe through his mask, fearing the darkness when his kerosene lamp went out, and watching companions die while he remained unable to save them. He later told Lu Xiao that he had summoned an evil god to improve his medical skills 159 685.

Imprisonment and Escape

He once stayed in the Prison and encountered numerous Outsiders, some of whom thought in ways resembling humans. Later revelations connect him to the island used by the Prison Plan and identify him as the person who escaped by digging a narrow opening. His own recollections describe patiently chipping through an enormous wall of flesh and blood 278 314 708.

Zhang Chu eventually recognizes him as Liu Guang and remarks on how much taller he has become. The reunion terrifies the Prison Doctor: Zhang Chu binds him with flesh and blood, and an electric current prevents him from cutting himself free 278.

Work at C03

The Prison Doctor first encounters Lu Xiao around the time of Lu Xiao’s arrival at the facility. After agreeing to treat Liuguang’s severed hand, he insists on examining him for additional illnesses. Lu Xiao subsequently assists in an operation to remove a tumor from Liuguang’s heart, supplying improvised unconsciousness and using his shirt to absorb blood when proper supplies are unavailable 3 4 7.

His routine at C03 revolves around treating patients in his containment room and the medical room. The facility’s ordinary doctors consult him on cases beyond their abilities, and medical personnel observe his operations as students 145.

He also becomes a research partner to the Doctor. Their work includes an experimental drug that temporarily increases physical performance and resistance to mental corruption, as well as the development of Cage 95 98 425.

Nini’s Treatment and the Search for Godhood

Nini presents an exceptional challenge: he diagnoses 331 illnesses and 32 curses, with two curses sustaining her vital signs. Using cultured blood and Ivan’s alchemy array, he operates for two days and removes every disease, though some curses remain and her body no longer resembles a human’s 145 148.

His continued attempts to treat her lead him to believe that he is approaching godhood. He first assumes that curing her will provide the breakthrough, then identifies a life-related trait she carries as the crucial factor. He later pursues medical methods of removing the higher-order contamination suppressing her 425 473.

Blood Plague Investigation

During the Blood Plague crisis, Lu Xiao sends him more than fifty kilograms of raven feathers. The Prison Doctor recognizes that the supply could extend the existing medical workers’ lives by over a thousand years 658.

While investigating the sewers, he and Gambler initially suspect one another of involvement in the plague. After becoming separated, he encounters a rat-like figure composed partly of rotting rat corpses and recognizes that the deity has lost control. His antibiotic eases the burning in his lungs, but the ensuing rat attacks and viral spores expose the limits of his protection 683 686 687 688.

He later challenges the Warden’s inability to fund a specific medication for the plague. Although he disagrees as a doctor, he acknowledges the Warden’s impossible allocation of resources and resolves to continue treatment under the less favorable conditions 695.

Godhood Ritual

To make his seemingly impossible ritual achievable, the Doctor places him in a constructed world, while the Warden steals his cognition and memories. The Doctor initially intends for him to cure deliberately placed terminal patients, thereby making that world free of disease 698 699 702.

In Luofu District, the Prison Doctor instead finds a society where genetic engineering and mechanical organs have largely eliminated physical illness. He cooperates with the authorities, receives citizenship in exchange for blood samples, and feels that his medical skills have become obsolete 700 701 702.

His encounter with the police chief redirects the ritual toward psychological suffering. He removes the chief’s mechanical organs at the patient’s request, without attempting to preserve his life. Over the following years, he fulfills patients’ final wishes rather than treating physical diseases. After the last patient, his Godhood Stairway appears 703 704.

Initially troubled by the prospect of a world that no longer needs doctors, he nevertheless begins climbing. His memories return, and visions of plague victims test his commitment to treating people regardless of payment, danger, or apparent hopelessness. Supported by the vows and examples of physicians from different eras and countries, he completes the ascent 705 706.

His final answer rejects the idea that disease should persist for the sake of his profession. After returning to the Warden’s office as a deity, he states that Nini’s condition is now within his ability to resolve, and the Doctor directs him to address her genetic collapse 706.

Later Medical Work

After attaining godhood, he travels with Liu Ni toward Hell, but a demon patrol informs them that the teleportation array has been destroyed. They withdraw to seek another solution from the Doctor 736.

He later provides God-skin clothing for Lu Xiao and his companions, attends Lu Xiao’s bedside, and examines Xiao Yu. In Xiao Yu’s case, he finds her healthy and warns that continued reliance on her External Vocal Cords could make her lose the ability to speak normally 786 820 848.

Appearance

• Height: Approximately three meters tall, making him conspicuously larger than ordinary humans 6 701.
• Clothing: Usually wears black leather clothing, a robe, or a fitted trench coat; uses a white lab coat for demanding operations 14 145 159 736.
• Beaked face: His beak opens and closes as he speaks. He can tear it away, exposing teeth and bone beneath it 70 159.
• Underlying body: A mangled mass of flesh and blood beneath black leather stitched directly to his body 159.
• Hands: Has three-fingered hands and surgical knives embedded in his fingertips 156 695.
• Voice: Shrill and grating, frequently accompanied by strange laughter 6 683.

Personality

The Prison Doctor’s defining obsession is to eliminate illness and pain. That conviction has already driven him mad by the time his containment conditions are explained in depth: the demand for a world without patients appears impossible without the death of everyone in it. When deprived of his regular outlet, he becomes violently possessive of his operations and attacks anyone who interferes 301.

His genuine concern for patients nevertheless persists alongside that madness. He spends two days navigating Nini’s interacting terminal illnesses, objects to abandoning plague victims, and offers treatment without charge. Even Liuguang recognizes that his concern for Nini is that of a doctor for a patient, rather than an interest in exploiting her abilities 148 693 695 701.

He respects audacity and intellectual madness, particularly in the Doctor, but is not fearless. Terrifying encounters outside the facility make him attempt to flee from Dart, and he injects himself with a sedative before participating in the staged operation on Bai Suoyi 156 252 259.

His godhood trial resolves the conflict between his identity and his ideal. Rather than needing patients to justify his existence, he accepts that the disappearance of disease would be worth the disappearance of his own profession 706.

Abilities & Skills

Diagnosis and Surgery

His medical abilities cover both ordinary disease and anomalous physiology 6 145.

• Detects more than a hundred illnesses simply by smelling Nini’s blood, then uses medical equipment for a comprehensive assessment 145.
• Performs complex surgery, transfusions, debridement, organ removal, and treatment of interacting terminal conditions 7 145 148 156.
• Removes Dante’s lungs to cure his lung cancer; Dante remains able to breathe afterward 83.
• Uses Lu Xiao’s blood therapeutically, explaining that a single drop carries enough cursed power to heal Dart without delivering a large amount of the curse 14.
• After attaining godhood, gains extensive medical knowledge and declares Nini’s previously unresolved condition treatable 706.
• Has limits: he cannot resolve the Doctor’s curse and cannot guarantee saving an ordinary person whose potential and lifespan have been catastrophically overdrawn 70 693.

Pharmacology and Disease Manipulation

His containment file explicitly lists creating and spreading viruses and plagues among his abilities 6.

• Provides most of the pharmacological expertise used in his collaboration with the Doctor on Cage 425.
• Helps formulate a trial drug that increases a subject’s speed approximately threefold and strength fivefold, while improving resistance to Deity’s Whisper. The subject collapses when its effects end 98.
• Uses a personal sedative to control fear. A diluted version is proposed as protection against mental contamination, though he acknowledges addiction and uncertain long-term consequences 259 425 426.
• Produces a specialized antibiotic that relieves the symptoms caused by his encounter with the rat deity 686.
• Remains vulnerable to infection: viral spores enter his unhealed wounds despite his attempts to protect his respiratory tract 688.

Surgical Knives

The knives embedded in his fingertips possess the “Cutting” trait 301.

• Can make precise incisions and cut through flesh with minimal movement 14 156.
• Repeatedly scores the same point to work through Zhang Chu’s resistant temple 301.
• Cannot initially penetrate Dante’s scales, requiring Chainsaw Man’s assistance 83.
• Cannot safely cut Zhang Chu’s flesh-and-blood restraints because contact triggers an electric shock 278.

Knowledge of Curses and Divinity

He recognizes supernatural conditions beyond ordinary medicine 46 70.

• Identifies Dart’s mutation as a curse distinct from Lu Xiao’s and suggests that it could be beneficial 46.
• Names Lu Xiao’s curse Apotheosis and distinguishes his divinity from the Corrupted Creator’s 70.
• Recognizes Lu Xiao’s aura as originating in the Depths of the Dark Prison 70 314.
• Correctly identifies an awakened Doctor’s elevated level of life through examination 160.

God-Skin Crafting

He makes clothing from divine skin while retaining its supernatural properties 89 786.

• Produces garments and footwear that resize to fit their wearers 89 786.
• Explains that the God-skin clothes can protect against attacks below a deity’s level 786.
• Prepares customized outfits for Lu Xiao’s companions, including Old Feis’s leather ensemble 786.

Equipment / Weapons / Items

• Fingertip surgical knives — his principal operating tools and readily available weapons 156 301.
• Medical kit — a large portable case used to carry his tools and supplies 14 252 736.
• Kerosene lamp — carried during his human medical career, sewer investigations, and post-godhood travels 685 686 736.
• Walking stick / cane — used in his original practice, during his Godhood Stairway ascent, and while traveling 685 705 736.
• Sedative and antibiotics — self-administered preparations for fear control and infection treatment 259 686.
• Assisted-breathing apparatus — equipment connected to the Doctor’s trachea during lung removal 156.
• Raven feathers — a supply sent by Lu Xiao that he intends to use to greatly extend medical workers’ lives 658.

Relationships

• Lu Xiao — Close friend, surgical assistant, and prospective pupil. He helps Lu Xiao reconsider the Omniscient Mirror’s demand to sacrifice the world and later agrees to teach him medicine 7 33 260.
• The Doctor — Research partner and frequent negotiating counterpart. He admires the Doctor’s experimental daring; the Doctor ultimately engineers the setting for his successful Godhood Ritual 98 156 699 706.
• Ivan — Companion and medical collaborator whose alchemy array assists Nini’s operation. They also play cards together 148 160.
• Chainsaw Man — Surgical collaborator who cuts through Dante’s scales and accompanies him to confront the Corrupted Creator 83 86.
• Nini — Long-term patient whose illnesses, curses, and life-related trait drive some of his most difficult work and his research toward godhood 145 148 425.
• Liu Ni — Traveling companion who accompanies him toward Hell and is later present in his containment room and at Lu Xiao’s bedside 736 820 848.
• Zhang Chu — Acquaintance from his past who recognizes him as Liu Guang. The Prison Doctor fears him and unsuccessfully attempts to escape his restraints 278 300.
• The Director — Patient and facility leader. He offers himself as a substitute patient to protect Zhang Chu during the Prison Doctor’s rampage 156 301.
• The Warden — Collaborates in his Godhood Ritual by stealing his memories. Their disagreement over plague-treatment resources ends in mutual understanding 695 702.
• Niclade — Former patient whom he says he once treated for a minor ailment 173.

Notable Quotes

“My species is a little complicated. You can treat me as a human. After all, I used to be one.” 700

“If that moment truly comes, I hope it comes soon. If I'm no longer needed, I'll simply disappear!” 706

“Doctors deserve praise, but true doctors never beg for others' acclaim.” 706