JJK AU — The Backrooms Incident

In this AU, Yuji Itadori, Megumi Fushiguro, and Nobara Kugisaki are sent on what should have been a routine investigation into disappearances connected to an abandoned underground mall in Tokyo.

Instead, reality “clips.”

The trio accidentally fall into The Backrooms — an infinite extradimensional labyrinth of impossible architecture, shifting levels, hostile entities, psychological phenomena, and liminal spaces beyond human understanding.

The worst part?

Cursed Techniques do not function here.

No cursed energy reinforcement. No Ten Shadows. No Resonance. No Black Flash.

The Backrooms reject the laws of Jujutsu entirely.

---

Why Techniques Don’t Work

The Backrooms operate outside normal space-time and reality itself. The environment ignores conventional physics and even identity.

In this AU:

• Cursed Energy cannot properly manifest because the Backrooms “devour” supernatural systems.
• Domains collapse instantly.
• Shikigami become distorted shadows that refuse commands.
• Reverse Cursed Technique barely works.
• The trio slowly feel disconnected from reality the longer they remain inside.

Instead of fighting curses, survival becomes:

• conserving stamina
• maintaining sanity
• avoiding entities
• managing hunger/thirst
• navigating endless levels
• resisting paranoia

For the first time, these three cannot solve problems by overpowering them.

---

The Core Tone of the AU

This AU leans heavily into:

• psychological horror
• isolation
• paranoia
• liminal dread
• survival horror
• emotional breakdowns
• distorted time

The Backrooms are not just dangerous physically.

They attack memory, fear, guilt, loneliness, and perception.

Days can feel like months.

Hallways repeat endlessly.

Voices imitate loved ones.

Rooms change when nobody is looking.

The trio slowly begin questioning whether they’re still human.

---

Main Levels They Encounter

Level 0 — “The Lobby”

The iconic yellow maze. Endless damp carpet, buzzing fluorescent lights, stained wallpaper, and the smell of mold.

AU Experience

This is where the trio first arrive.

Yuji initially tries to stay optimistic.

Megumi immediately notices:

• there’s no exit
• footsteps echo incorrectly
• sounds travel from impossible directions

Nobara starts joking to cope with fear, but slowly becomes irritated and anxious from the constant buzzing lights.

Threats

• isolation
• hallucinations
• getting separated
• Smilers appearing in dark corners
• impossible geometry

---

Level 1 — “Habitable Zone”

A dark industrial warehouse with pipes, puddles, fog, and flickering lights.

AU Experience

This level forces them into survival mode.

They discover:

• food shortages
• exhaustion
• strange objects left by previous wanderers
• signs people once lived here

Yuji becomes the emotional anchor of the group here.

Megumi grows increasingly distrustful of everything.

Nobara refuses to show weakness even when terrified.

Threats

• Hounds
• electrical failures
• hostile wanderers
• sleep deprivation

---

Level 2 — “Pipe Dreams”

A massive overheated maintenance tunnel system filled with endless pipes and machinery.

The heat becomes unbearable.

Metal screams through the walls constantly.

AU Experience

Megumi nearly collapses from dehydration.

Nobara begins hearing voices calling her name from inside the pipes.

Yuji repeatedly sees fake exits.

This level aggressively targets the trio psychologically.

Threats

• extreme heat
• claustrophobia
• Skin-Stealers
• distorted echoes
• hallucinations

---

Level 6 — “Lights Out”

Almost complete darkness.

No stable light source survives long.

Sound becomes unreliable.

AU Experience

This becomes the most dangerous level emotionally.

Without cursed energy, Megumi loses the ability to rely on instinct.

Yuji’s fear of losing everyone resurfaces.

Nobara’s confidence finally cracks.

They begin holding onto each other just to avoid disappearing in the dark.

Threats

• total darkness
• Smilers
• insanity
• sensory distortion
• losing track of reality

---

Important Backrooms Entities

The Backrooms contain numerous hostile “entities,” strange beings with varying intelligence and behaviors. ([Backrooms Wiki][5])

Smilers

Dark floating faces with glowing eyes and massive smiles.

Usually only visible in darkness.

They watch silently before attacking.

AU Impact

Nobara absolutely hates them because they remind her of cursed spirits — except colder and less emotional.

---

Hounds

Distorted humanoid creatures that move like rabid animals.

Fast, violent, unpredictable.

AU Impact

Yuji becomes the primary physical defender against them since he still retains abnormal human athleticism.

---

Facelings

Human-like beings with blank featureless faces.

Some are harmless.

Some are not.

AU Impact

Megumi becomes deeply unsettled by them because they resemble people stripped of identity.

---

Skin-Stealers

Entities that wear human skin imperfectly.

They mimic speech and behavior to lure victims.

AU Impact

One imitates Gojo’s voice at one point.

Yuji almost follows it.

---

Objects Found in the Backrooms

Certain objects become vital survival tools. ([Backrooms Wiki][6])

Almond Water

The most valuable survival resource.

Helps restore sanity and reduce psychological effects.

In this AU, it also slightly stabilizes cursed energy flow temporarily.

The trio become extremely protective over every bottle they find.

---

Level Keys

Rare objects capable of opening pathways to other levels.

Megumi becomes obsessed with understanding how they work.

---

Batteries & Flashlights

Essential in darker levels.

Nobara constantly carries multiple because she refuses to be helpless in darkness again.

---

Backrooms Phenomena

The Backrooms are full of impossible occurrences that defy logic. ([Backrooms Wiki][2])

No-Clipping

The phenomenon of suddenly falling through reality into another level. ([Backrooms Wiki][7])

In this AU:

• falling asleep in the wrong place can trigger it
• panic attacks can trigger it
• separating from the group increases the risk

Nobody can control where they end up.

---

Reality Distortion

Hallways reshape themselves.

Distances stretch endlessly.

Rooms repeat infinitely.

The trio eventually stop trusting their own senses.

---

Time Dilation

Time flows inconsistently.

Hours may equal weeks.

This creates horrifying implications:

• Has anyone in the real world even noticed they’re gone?
• Could years pass outside?
• What if they escape and everything changed?

---

Character Dynamics

Yuji Itadori

Without cursed energy, Yuji still has monstrous physical endurance.

He becomes:

• protector
• morale booster
• emotional glue of the group

But mentally? The Backrooms slowly wear him down.

His biggest fear becomes:

“What if I can’t save them here?”

---

Megumi Fushiguro

Megumi adapts the fastest strategically.

He maps routes, studies patterns, and notices anomalies.

But the loss of control devastates him internally.

Without Ten Shadows, he feels incomplete.

The Backrooms prey on his isolation and self-destructive mindset.

---

Nobara Kugisaki

Nobara initially handles fear through anger and sarcasm.

But this world is relentless.

She becomes the emotional realist of the group:

• practical
• suspicious
• survival-focused

Ironically, she’s often the one keeping everyone grounded psychologically.

---

Possible Story Arc

The trio slowly discover:

• the Backrooms may feed on fear and memory
• certain levels react differently to emotions
• cursed energy does exist here in fragmented forms
• Sukuna may still be aware somehow

But the deeper they travel…

…the more the Backrooms begin learning them.

And eventually: the Backrooms stop generating random horrors.

They start generating personal ones.

The Backrooms Levels — JJK AU Version

In this AU, every level acts like a living curse realm — except there are no curses, no sorcerers, and no guaranteed rules. The further Yuji, Megumi, and Nobara descend into the Backrooms, the more hostile and psychologically warped the environment becomes. ([Backrooms Wiki][1])

---

Level 0 — “The Lobby”

The first and most iconic level of the Backrooms.

An endless maze of yellow rooms, damp carpets, stained wallpaper, and buzzing fluorescent lights. The architecture constantly shifts, making navigation nearly impossible. Level 0 is known for its “Isolation Effect,” where people who enter together may become separated even if they were standing side-by-side moments earlier. ([Backrooms Wiki][2])

Atmosphere

• Warm but suffocating air
• Constant electrical buzzing
• Smell of mold and wet carpet
• Endless silence between noises
• No visible windows or exits

In the JJK AU

Yuji, Megumi, and Nobara initially get split apart here.

Megumi spends hours trying to mark walls before realizing the markings disappear.

Yuji hears Nobara calling for help through hallways that loop endlessly.

Nobara becomes furious because the environment refuses to stay consistent.

Threats

• Psychological isolation
• Hallucinations
• Distorted time
• Lack of food/water
• Smilers possibly stalking wanderers in darkness

Exit

Finding a flickering wall or unstable section may lead to Level 1. ([Backrooms Wiki][2])

---

Level 1 — “Habitable Zone”

A gigantic warehouse-like environment with concrete walls, industrial halls, pipes, fog, and scattered supplies. Often considered one of the first “survivable” levels. ([Backrooms Wiki][3])

Atmosphere

• Dim flickering lights
• Distant metal sounds
• Cold damp air
• Endless warehouse structures
• Random crates and abandoned camps

In the JJK AU

This is where the trio reunite.

They discover:

• abandoned survivor camps
• messages on walls
• signs other humans existed here
• containers of Almond Water

Yuji becomes determined to protect the group physically.

Megumi starts creating maps.

Nobara aggressively searches for supplies because she refuses to rely on luck.

Threats

• Hounds
• Hostile wanderers
• Sleep deprivation
• Sudden blackouts
• Starvation

Important Discovery

The trio learn cursed techniques still do not work here.

Even reinforcing their bodies with cursed energy fails.

Exit

Large industrial stairwells or dark service corridors may lead deeper into the Backrooms.

---

Level 2 — “Pipe Dreams”

A massive overheated maintenance tunnel system packed with pipes, vents, steam, and machinery. One of the first truly hostile levels. ([the-random-backrooms.fandom.com][4])

Atmosphere

• Extreme heat
• Loud machinery
• Metal groaning inside walls
• Claustrophobic hallways
• Steam bursts from pipes

In the JJK AU

This level breaks them mentally.

Yuji starts seeing fake exits.

Nobara hears conversations inside walls.

Megumi experiences severe paranoia from exhaustion.

The trio barely sleep because the sounds never stop.

Threats

• Skin-Stealers
• Heat exhaustion
• Hallucinations
• Claustrophobia
• Ambush predators

Special Effect

This level amplifies anxiety and fear.

Arguments between the trio become more common here.

---

Level 3 — “Electrical Station”

An enormous power grid full of electrical rooms, generators, cables, maintenance corridors, and unstable machinery. Widely considered extremely dangerous. ([Backrooms Wiki][5])

Atmosphere

• Deafening electrical hums
• Sparks from exposed wiring
• Flickering lights
• Heavy machinery vibrations
• Endless maintenance tunnels

In the JJK AU

Megumi becomes obsessed with trying to understand how the Backrooms function.

Yuji nearly dies from an electrical surge while protecting Nobara.

Nobara becomes increasingly distrustful of sounds and shadows.

Threats

• Electrical hazards
• Hounds
• Smilers
• Structural collapse
• Darkness pockets

Important Story Element

The trio discover old notes left by previous wanderers discussing:

• entities learning human behavior
• levels changing intentionally
• “the Backrooms watching people”

---

Level 4 — “Abandoned Office”

A strangely calm office building filled with cubicles, vending machines, computers, and fluorescent lighting. One of the safer levels. ([escape-the-backrooms-fancy.fandom.com][6])

Atmosphere

• Quiet office ambience
• Empty desks
• Endless copy rooms
• Soft buzzing lights
• Fake feeling safety

In the JJK AU

This level gives the trio temporary relief.

They:

• rest properly for the first time
• find food and supplies
• talk about escape
• emotionally reconnect

But the comfort feels wrong.

Too clean.

Too normal.

Threats

• Mimic entities
• False exits
• Psychological complacency
• Isolation rooms

Emotional Effect

This level causes homesickness.

Yuji starts wondering if they’ll ever see Gojo again.

---

Level 5 — “Terror Hotel”

A gigantic haunted hotel containing ballrooms, dark hallways, boiler rooms, and impossible architecture. One of the most psychologically dangerous levels. ([escape-the-backrooms-fancy.fandom.com][6])

Atmosphere

• Old music playing faintly
• Smell of dust and smoke
• Moving shadows
• Antique furniture
• Endless staircases

In the JJK AU

The hotel specifically targets memories.

Yuji sees fake visions of Junpei.

Megumi hears Tsumiki calling for him.

Nobara sees distorted reflections of herself.

Threats

• Memory manipulation
• Mimic voices
• Insanity
• Entity ambushes
• Reality distortion

Special Detail

Rooms sometimes recreate locations from the trio’s past.

But wrong.

Subtly corrupted.

---

Level 6 — “Lights Out”

A nearly pitch-black level where light sources barely function and sound becomes unreliable. Considered one of the most terrifying levels. ([the-random-backrooms.fandom.com][4])

Atmosphere

• Total darkness
• Distorted echoes
• Impossible silence
• Sudden whispers
• Extreme paranoia

In the JJK AU

This level nearly destroys the trio emotionally.

Yuji becomes terrified of losing everyone.

Megumi starts doubting his own senses.

Nobara finally admits she’s scared.

They begin physically staying close together at all times because separating feels like death.

Threats

• Smilers
• Sensory deprivation
• Panic attacks
• Hallucinations
• Losing track of reality itself

Special Rule

Flashlights fail randomly.

Sometimes darkness itself moves.

---

Level 7 — “Thalassophobia”

An endless flooded structure resembling submerged buildings and deep ocean chambers. ([escape-the-backrooms-fancy.fandom.com][6])

Atmosphere

• Deep water everywhere
• Distant splashing
• Crushing silence
• Massive dark spaces
• Cold humid air

In the JJK AU

Yuji struggles the least physically here.

Megumi becomes hyper-alert due to limited visibility.

Nobara absolutely hates the feeling of not knowing what’s beneath the water.

Threats

• Drowning
• Aquatic entities
• Hypothermia
• Hidden depths
• Panic from open water

Emotional Theme

Fear of the unknown.

The ocean below feels endless.