An Qingyu

Biodata

Feature	Details
Name	An Qingyu (安卿鱼)
Alias(es)	Secret Thief; Key of Doors; Yu Yi
Species/Race	Human; later revealed to be a fragment of the Gate of Truth, one of the Lovecraftian Three Pillars 1554
Gender	Male
Affiliation	Former Night Watchman and Vice-Captain of [Nightfall]; later acts independently in pursuit of the Key of Doors 1269 1583
Occupation/Role	Researcher, surgeon, dissector of “Mysteries,” and former Nightfall vice-captain
Status	Active; Supreme Realm and merged with the repaired Gate of Truth while remaining soul-bound 1946

Power Progression

Stage / Realm / Level	Chapter	Notes
Sea Realm (Lv. 68)	677	Yurina Takishiro’s level-based perception identifies An Qingyu as Lv. 68, corresponding to the Sea Realm.
Klein Realm	1249	Breaks through after rapidly dissecting the mysterious corpses available at Utopia.
Human Apex	1269	Surpasses Cao Yuan and Baili Pangpang in Mental Power; performs a multi-ability ritual to locate Lin Qiye in the Mist.
Supreme Realm	1946	Reaches the Supreme Realm after merging with the repaired Gate of Truth.

Background

An Qingyu initially refuses to join the Night Watchmen because their rules would restrict his experiments and prevent him from dissecting “Mysteries.” His stated goal is to uncover the world’s truth, regardless of how unsettling his methods appear. Lin Qiye nevertheless recognizes that An Qingyu had helped solve the Nanda Snake Demon case and the New Year incident, and chooses not to hand him over to the Night Watchmen. 224

After completing an isolated research project, An Qingyu deliberately surrenders himself as a “Secret Thief” so that he can enter the Abstinence Hall. His reasons are twofold: repaying his debt to Lin Qiye, who is confined there, and testing himself against Great Xia’s most secure superpowered prison. 283

Within the Abstinence Hall, An Qingyu studies the prison’s design, gathers intelligence, and collaborates with Lin Qiye on possible escape routes. When a one-eyed inmate attempts to murder him, An Qingyu patiently extracts information from the man before killing and dismembering him with the concealed forbidden item [Eerie Silk]. 289 300

He later becomes a Night Watchman and serves as the vice-captain of [Nightfall]. His research into Mystery anatomy repeatedly enhances his body and abilities, allowing him to rapidly rise through the cultivation realms. 749 1097 1269

Appearance

An Qingyu is a slender, scholarly-looking young man with a delicate face, black hair, and glasses. He is frequently associated with surgical tools, laboratory clothing, and a black coffin carried on his back. 289 385 798

• Usually wears transparent-lensed glasses; Lin Qiye associates them with his intellectual, reserved appearance. 289 1137
• Often wears a white lab coat while conducting research or surgery. 1097
• Later adopts a hooded black robe and displays cold gray eyes after his connection to the Gate of Truth deepens. 1616
• Has carried a Giant Beast head and manifested additional arms while using several abilities simultaneously. 1269
• Following his soul injury, he temporarily relies on a custom Mental Power-driven wheelchair. 1511 1513

Personality

An Qingyu is driven by an obsessive, clinical pursuit of truth. He regards corpses, divine power, Mysteries, and even his own body as sources of information to be analyzed. His fascination is not merely academic: he is willing to cut open his own finger to test blood loss, dissect dangerous entities, and expose himself to contamination if he believes the resulting knowledge is necessary. 224 749 1492

Despite his unnerving interests, he is not initially malicious. Lin Qiye considers him eccentric rather than inherently evil, and An Qingyu’s decision to enter the Abstinence Hall is motivated partly by gratitude and loyalty. He is calm under threat, highly observant, and usually speaks with measured precision. 224 283 288

Before his soul injury, An Qingyu is shy and low-key outside of research. Jiang Er’s influence gradually brings out a more open side of him, including his willingness to perform publicly and learn guitar. 1513 1537 1546

His contact with the Gate of Truth changes him profoundly. The knowledge beyond the Gate erodes his human aura and emotional responses, leaving him increasingly detached, calculating, and willing to make ruthless choices in the name of the “most correct” outcome. 1570 1583 1884

Abilities & Skills

The Only Correct Answer

An Qingyu’s core power allows him to deconstruct matter and Forbidden Zones, a capability tied directly to his nature as a fragment of the Gate of Truth. 1554

• Can analyze structures down to microscopic detail and reconstruct matter into different forms. 1618 1619
• Has turned massive doors into paper fragments and collapsed three-dimensional space around enemies. 1618 1144
• Can instantly kill close-range opponents by reconstructing their bodies; this method killed three Knight Commanders. 1617 1619
• Cannot reconstruct substances beyond his analytical limit, as shown when he failed to alter Lin Qiye’s body. 1619
• Can analyze residual energy, bloodlines, contamination, Spiritual Energy frequencies, and the composition of unusual objects. 879 1105 1624

Gate of Truth Authority

As a fragment of the Gate of Truth, An Qingyu can access powers related to space, time, transformation, and the Lovecraftian entity behind the Gate. 1554 1588

• Causes unconscious spacetime disturbances capable of transporting himself and Jiang Er across vast distances. 1560
• Can travel through space and escape through spatial-temporal distortions. 1580 1621
• Can summon the Gate of Truth and bargain with the entities beyond it. 1623 1830 1831
• Has perceived billions of timelines through the Gate and concluded that humanity has no path to victory in most of them. 1583
• Pays tangible prices for deeper access; one exchange extracts his emotions. 1831

Regeneration and Modified Physiology

An Qingyu has altered his body through repeated anatomical modifications and the traits harvested from dissected Mysteries. 749

• Regenerates shattered hands, destroyed flesh, and severed body parts rapidly. 557 1620
• Can survive severe damage by dispersing into rats or mist before reforming elsewhere. 1620 1866
• Possesses several poison-related Mystery traits and can produce poisonous mist from his own blood. 749
• Can reconnect contaminated body parts to himself in order to endure or analyze Lovecraftian whispers. 1493
• His regeneration does not prevent soul injury; damage to his soul impaired both his mobility and his calculation ability. 1502 1511 1512

Clone Creation and Body Transfer

After dissecting the Ten-Cut Ghost Child, An Qingyu gains the ability to create replacement bodies and be reborn through them. 1097

• A prepared clone can serve as a rebirth vessel after his main body dies. 1097
• Creating a clone requires extensive time and energy; even under ideal conditions, one takes at least four months to produce. 1097
• Creates self-aware Artificial Gods, including Yu San, using the body of a Supreme Realm Overgod. 1828
• Can swap souls with a clone through the Gate of Truth, bypassing Lin Qiye’s attempt to contain him in the Psychiatric Hospital of the Gods. 1828
• Artificial God bodies can wield Divine Laws, including Zeus’s lightning. 1828

Analysis, Surgery, and Research

An Qingyu is an exceptionally skilled surgeon and investigator whose deductions often guide his team through unfamiliar threats. 224 799

• Uses self-experimentation to verify evidence, including recreating blood-loss conditions with his own finger. 224
• Performs corpse modification and surgery, including work on Jiang Er’s body and an improvised brain operation on Lin Qiye. 799 1387
• Identifies distortions in timelines, currency, supplies, and social environments through small physical inconsistencies. 868
• Deciphers Lovecraftian whispers well enough to locate Lin Qiye and missing Great Xia Gods through a spatial rift. 1492 1502
• His logical reasoning and calculation were severely damaged by soul mutation, though he later shows partial recovery. 1512 1533

Combat Adaptation

An Qingyu combines reconstructed matter with analyzed Mystery abilities to fight unpredictably. 1144

• Uses frost, invisible threads, lightning, poison mist, spatial collapse, and body transformation in combat. 1144
• Can manifest extra arms to operate multiple rituals and abilities at once. 1269
• Uses highly concentrated reconstructed poison capable of driving even Sovereigns mad. 1619
• Favors preparation, substitutes, traps, and escape routes over direct confrontation. 1617

Equipment / Weapons / Items

• [Eerie Silk] — Invisible thread concealed inside his body to bypass Abstinence Hall searches; used to kill and dismember the one-eyed inmate. 289
• Black Coffin — Carries Jiang Er’s body and assists in stabilizing her magnetic field. 798
• Surgical scalpels — Uses specialized glowing scalpels for dissection and research. 385
• Frost Greatsword — A weapon he can materialize, including for self-amputation during dangerous experiments. 1493
• Custom wheelchair — Built by Cao Yuan and propelled through Mental Power after An Qingyu loses control of his legs. 1512 1513
• Glasses — A signature part of his earlier scholarly appearance; he is notably without them after his later transformation. 1137 1604

Relationships

• Lin Qiye — Ally, friend, captain, and later adversary. Lin Qiye protects An Qingyu from arrest, accepts his help in the Abstinence Hall, and relies on him as Nightfall’s vice-captain; later, Lin imprisons him in Ward No. 6 after An Qingyu’s break with the team. 224 300 1269 1817
• Jiang Er — Closest companion. An Qingyu maintains her body, stabilizes her magnetic field, and repeatedly risks himself to protect or restore her; Jiang Er remains devoted to him through his paralysis, soul damage, and transformation. 798 1512 1556 1571
• Cao Yuan — Nightfall teammate and trusted friend. Cao Yuan agrees to monitor An Qingyu during his Lovecraftian-whisper experiment, later builds him a wheelchair, and eventually confronts him when he leaves Heavenly Court. 1492 1512 1583
• Shen Qingzhu — Nightfall teammate who confronts An Qingyu after his departure from the team and refuses to let him proceed unchallenged. 1616
• Li Yifei — Formerly a source of research interest and later An Qingyu’s assigned caretaker in Ward No. 6. Li Yifei remains deeply traumatized by An Qingyu’s past actions. 1817
• Zhou Ping — Former teacher. Zhou Ping allows An Qingyu to leave captivity once, but warns that his sword will show no mercy should they meet as enemies again. 1823
• Chaos — Temporary collaborator and later open antagonist. They divide a mirror world while awaiting the Key of Doors’ revival, but An Qingyu later openly rejects Chaos’s designs. 1604 1883

Story Role / Major Arcs

Independent Researcher and Abstinence Hall Inmate

An Qingyu begins as an unaffiliated investigator seeking unrestricted access to Mysteries. His alliance with Lin Qiye develops after he helps with the Nanda Snake Demon case, then deepens when he intentionally enters the Abstinence Hall to repay Lin Qiye and challenge himself against its security. 224 283

In the prison, he establishes himself as dangerous and methodical by using [Eerie Silk] to kill an aggressor, then works with Lin Qiye to map the facility and expose the suspicious treatment Lin receives from Sunshine Psychiatric Hospital. 289 300

Nightfall Vice-Captain

After becoming a Night Watchman, An Qingyu grows rapidly through dissection, biological modification, and field research. At Utopia, he reaches the Klein Realm; shortly afterward, he advances to Human Apex and uses several abilities at once to locate Lin Qiye in the Mist. 1249 1269

His research skills become central to Nightfall’s operations. He identifies enemy infiltrators, analyzes spiritual energy and contamination, and uses his altered biology to counter poison-based threats. 749 879 1031 1105

Soul Injury and Recovery

To locate Lin Qiye and the Great Xia Gods, An Qingyu connects himself to Lovecraftian whispers despite the risk of corruption. He succeeds, but his soul is badly injured and he falls into a coma. 1492 1502

After awakening, he cannot feel or control his legs, and testing reveals that soul mutation has severely reduced his logical reasoning and calculation ability. Cao Yuan provides a wheelchair, Jiang Er remains at his side, and An Qingyu slowly regains portions of his former confidence and processing power. 1511 1512 1513 1533

Gate of Truth Revelation

The Heavenly Court reveals that An Qingyu is a fragment of the Gate of Truth. His ability to deconstruct matter and Forbidden Zones strengthens the Gate’s return, while the Mi Go are drawn to his aura and sacrifice themselves to accelerate its revival. 1554

After an uncontrolled spacetime disturbance transports him and Jiang Er into the Mist, An Qingyu comes into direct contact with the Gate. The knowledge he gains nearly erases his human aura and leaves him increasingly detached from the people around him. 1560 1570

Departure from Nightfall

Believing that he has seen humanity’s inevitable defeat across countless timelines, An Qingyu leaves Nightfall to seek what he considers the only correct choice. Zuo Qing disowns him, while Cao Yuan attempts to stop him at the South Heaven Gate. 1583

He later cooperates with Chaos to create a mirror-world refuge and states that the Key of Doors will require approximately four years to revive. 1604

Capture, Artificial Gods, and Escape

Lin Qiye eventually traps An Qingyu in the Psychiatric Hospital of the Gods and assigns him to Ward No. 6. An Qingyu remains calm in confinement and acknowledges Lin Qiye’s strategic skill, while quietly implying that he has prepared contingencies. 1815 1817

Those contingencies include Artificial Gods such as Yu San. By swapping souls with his self-aware clone through the Gate of Truth, An Qingyu escapes the hospital’s confinement and resumes his independent plans. 1828

Supreme Realm

An Qingyu later uses the Gate of Truth and Divine Beast blood in attempts connected to Jiang Er’s restoration. The price of one exchange is his emotions, intensifying his detachment. 1830 1831

By the time he reaches the Supreme Realm, he has merged with the repaired Gate of Truth and remains involved in a larger struggle with Chaos. He later meets Lin Qiye across the River of Time and reminds him that their chess match remains unfinished. 1946 1950

Notable Quotes

“I just want to dissect ‘mystery’ to my heart’s content and understand the truest side of this world. What I pursue is truth!” 224

“My favors carry a lot of weight.” 283

“In the billions of timelines I’ve seen, humanity has no chance of victory. I simply made the most correct choice.” 1583

“Your first move has been played... Next, it’s my turn to make a move.” 1828

Trivia

• An Qingyu once told Old Dog Wu that he was more interested in dissecting him than in choosing between two fish in a dream. 302
• He initially struggles to control Cao Yuan’s wheelchair, repeatedly crashing into walls before finding the experience enjoyable. 1513
• He asks Li Yifei to teach him guitar during his recovery. 1537
• Lin Qiye once lies about An Qingyu’s future appearance to ease his anxiety, concealing the cold and emotionless figure he had actually seen. 1137