I Bought a Rulebook, It Turned Into a Grimoire (1)
TRPG.
Short for Tabletop Role-Playing Game, it’s a game where everyone gathers around a table to act out their assigned roles. You roleplay scenarios, immerse yourself in character, recite dramatic dialogue, and stake your fate on the roll of the dice.
And right now, I’d just bought a rulebook to finally break into that world!
Secondhand, of course.
Ah, what a thrilling moment.
And the system? CoC—Call of Cthulhu!
Cosmic horror, irresistible death, a universe where humans are portrayed as lesser than mere ants... and yet, paradoxically, a setting where the dazzling brilliance of the human spirit can truly shine. It was, quite simply, my exact cup of tea.
To be honest, I hadn’t actually read Lovecraft’s original works. I’d only skimmed surface-level summaries on the internet and browsed wikis. But who cares? I bought the rulebook so I could finally dive in headfirst!
Secondhand, of course.
I was so hyped that I couldn't even remember what the seller looked like. Clutching the rulebook to my chest, my steps felt so light on the walk home that I felt like I was floating on air.
Ugh, man, what if someone sees me?
‘Wait, is that guy carrying a book?’
‘What is that? Huh? Isn't that Call of Cthulhu? Holy crap, buying that rulebook... he must be a hardcore TRPG veteran.’
‘Ah, please, no photos, you're embarrassing me.’
‘What's with that weird voice?’
Total delusion. Absolutely unhinged.
Still, that was just how excited I was.
Yeah, so thrilled that I let my guard down completely—right up until the moment a commercial signboard plummeted from the building above.
CRUNCH—!!
I didn't even have time to register my own death.
Bubbles rising.
Iridescent bubbles filled the expanse in every direction. They laughed, wept, shrieked, mourned, and grieved, threading through one another with strands of every color, weaving together, inverting, and twisting anew to form an eternal infinity.
There, I was a mere speck of dust, unworthy of becoming even a single drop of foam.
Grieve.
Do not cry out.
For in this hollow void of a cosmos, every sound fades into absolute silence.
Then, I was torn from the froth. It felt as if someone had seized my body and ripped me straight out of the heart of the bubbles. Helplessly dragged by that colossal power, all my eyes could see was an infinite sea of spheres.
And into one of those bubbles, I was hurled.
Connecting to System...
Abnormal access confirmed.
...Negotiating...
System addition complete.
This world is now yours.
“Guh-ack!”
With a jolt that rattled my skull, I wrenched my heavy eyelids open. What the hell? What just happened?
I whipped my head around to assess the situation, but it was just my usual studio apartment. That stale, suffocating odor, the damp semi-basement stench that permeated every corner—it was unmistakably my place.
...Wait, I don't remember opening the door and walking in?
It wasn't like I’d gone out drinking heavily with friends. What could possibly cause a blackout in broad daylight? All I remembered was buying a rulebook secondhand, and on my way back... on the way...?
“Hurk—!!”
In that instant, the memory resurfaced, flashing violently through my mind: my own death. The building's signboard had struck dead-center atop my crown. The sheer weight alone would have crushed me, but it had to plunge down corner-first, pulverizing my skull.
“BLEUURGH—!!”
Clamping a hand over my mouth, I sprinted to the bathroom and heaved into the toilet bowl.
That sickening agony of being crushed and shattered... People always said you wouldn't feel pain if your head was smashed first, but they were full of shit. I had experienced my death in vivid, excruciating detail. The pain, the final image of myself burned onto my retina as my eyeballs popped out—every single bit of it had been real.
“...Wait, what?”
Then why was I alive?
A dying hallucination? An inner mindscape? The afterlife?
Desperate to understand what was going on, I hastily rinsed my mouth at the sink and stepped back into the room.
“....”
The stale air hadn't changed. Being a semi-basement, the faint sunlight trickling down from the stairwell was the exact same, too. The date, the time, my phone—everything was completely intact. I hadn't caught the exact minute, but judging by the afternoon light, it was roughly the time I should have arrived home after finishing the secondhand deal.
“...Wait, does that mean...?”
Was it all just a dream? A premonition?
I walked back to my desk to search for the final piece of evidence.
The rulebook.
“If this is here, then I definitely bought it, right?”
I opened the secondhand marketplace app to check, but there was no record. The chat history with the seller, even the listing itself—everything had vanished without a trace. His manner temperature had been 19.37°C, so I’d trusted him somewhat... Wait, I actually got the book, so it wasn't a scam, right?
Still...
Was the rulebook always like this?
The terrifying silhouette of a colossal monstrosity and the title that should have been emblazoned across the cover were nowhere to be found. Instead, the entire front was coated in pitch-black, ink-like darkness. And from the pages wafted a bizarrely pungent, nauseating fishy stench.
Did someone boil this thing? No, even if you boiled paper, it wouldn't reek like a stagnant swamp. It smelled distinctly of raw fish...
The moment I lifted the book to check its contents—
Ding!
A cheerful chime rang out. It wasn't my phone. My phone didn't make that sound.
—Honk-honk!
Yeah, that was my notification ringtone. Then what the hell was that chime?
The answer materialized right before my eyes in the form of a floating blue window.
Right...
A status screen.
“...Am I finally losing my mind?”
Despite my skepticism and frantic denial, the system window displayed a single, mechanical sentence.
You have awakened as a Grimoire Mage.
“Grimoire Mage?”
Ding!
Whether reacting to my words or updating on its own, the status window that had just defined me chimed again and changed its contents.
It was absurdly minimalist and bare-bones.
“Wait, where are the stats? No strength? No agility?”
I tapped at the screen with my finger, looking to see if there were any detailed descriptions hidden inside.
“Whoa, what the hell?”
No matter how hard I pressed, there was zero physical resistance. Yet, I could distinctly feel a sensation of interaction, which suggested this wasn't just a mental breakdown. Actually, scratch that. The fact that I was feeling it probably meant the chances of me having gone completely insane were even higher.
“...I’m not crazy!!”
I balled my fists tight and swung straight at the status screen. If I wanted to prove I wasn't mentally ill, I had to shatter this hallucination!
Whoosh—whoosh!
My fist phased cleanly through my name, passing harmlessly through my level and class. Mocking my desperate efforts, the status window didn't so much as flicker.
“I am NOT!! Insane!!”
Humans are evolving creatures, animals capable of utilizing tools.
I brought the rulebook in my left hand crashing down onto the floating screen.
CLANG—!!
?
It made impact.
The status window hovering before my eyes took a direct hit from the rulebook and went flying, crashing onto the linoleum floor.
Wait, how the hell did that work?
Thinking back, the status window had popped up the exact second I touched the rulebook. And my awakened class was Grimoire Mage. Does that mean... this rulebook is actually a grimoire?
Bzzzt—crackle—fizz—
The status window lying on the floor sparked with static, glitched out, and vanished into thin air.
I swept my foot across the spot where it had been. Once I confirmed it was completely gone, I rushed straight to my desk and booted up my computer.
“I’ve lost it... Fuck, I’ve completely lost my marbles.”
Status windows? Grimoire Mages? A rulebook turning into an actual grimoire? I was officially out of my gourd.
I frantically prepared to search for mental disorders involving status windows and symptoms of schizophrenia. Before I checked myself into a psych ward, I needed to know exactly what kind of breakdown I was suffering from.
And yet...
“...Huh?”
The news headlines that greeted me on the homepage were subtly different from the ones I was used to.
“S-Rank Hunter Kang Baek-hwan Deploys to France to Raid S-Rank Gate! What Will the Outcome Be?”
“C-Rank Hunter and Pop Singer Ellie Announces New Track Release From Inside an Other-Dimensional Gate...”
“What the hell?”
Hunters? Like, those hunters?
Gates?
I clicked through the articles one by one, rapidly skimming through the alien terms—familiar from fiction, yet absurdly out of place in reality.
After thirty minutes of frantic browsing...
“....”
My head throbbed so hard I slammed my forehead onto the keyboard.
There was one piece of good news: thankfully, that status window hadn't been schizophrenia or a psychotic hallucination. The other news, however, was that this world had Gates—and Awakened individuals who cleared them: Hunters.
“Why?”
Had I somehow lived twenty-five years without noticing this? Was my entire hometown some massive film set, and was my life being broadcast as a drama like The Truman Show?
No, impossible.
My studio apartment, my resident registration number—wait, why is it called a 'Citizen Registration Number' here? My driver's license, my phone—everything was legitimately mine.
“...No, there's still one more thing to verify.”
I rapidly flicked the mouse and navigated through my file directories.
“....”
My porn folder was intact. Even the video I downloaded yesterday was sitting right there...
Wait, what is this?
📁 D-Cup Cat Beastgirl and....mp4
Beastfolk exist too?!
Wait, why the hell is this in my folder?
No, that wasn't what mattered right now. Right now, only one thing was critical.
“...Hmm. This definitely warrants a thorough, meticulous investigation.”
I reached over and grabbed the tissues sitting in their usual spot.
To summarize: beastfolk existed in this world.
Furthermore, society was primarily sustained by harvesting resources from Gates.
And beastfolk existed.
Hunters routinely raided Gates connected to other dimensions to farm a resource known as magic stones.
There were a lot of beastfolk.
However, not everyone could become a hunter. Only those who achieved 'awakening'—sensing mana—could perceive a status window.
The variety of beastfolk was remarkably diverse.
I felt as though my horizons had broadened immensely. I suppose you could say my eyes had been opened to a whole new world.
Leaving the computer on, I placed the rulebook on the floor and sat down across from it, staring it down.
A rulebook. The object that had triggered the status window when touched, and the very item that had physically battered a screen my bare fists couldn't even graze.
To be frank, at this point, I wasn't even sure if this thing was a rulebook. Why was I even perceiving it as one? Neither its appearance nor its smell resembled a book in the slightest.
What system was it again...? Oh, right...
“Ah, yeah. Cth—”
In that split second.
Just as that name was about to slip past my lips—
“....”
An incomprehensible force clamped my lips shut. Every primal survival instinct within me screamed a deafening alarm: DO NOT SPEAK IT.
Sweat instantly drenched my body, and capillaries burst in my eyes with tiny pricks of agony. An overwhelming, suffocating gaze—there was no other way to describe the sheer pressure bearing down on me. I was struck with absolute, bone-deep certainty that at any moment, a colossal finger could descend from above and crush me into paste like an insect.
....
Slowly, the gaze withdrew.
Only after that unfathomable presence stopped dissecting and excavating every fiber of my being did I finally let out a ragged gasp.
“...Haaah... haaah...”
My eyes stung with broken blood vessels, and goosebumps erupted along my skin as my hair stood on end.
A grimoire, a Grimoire Mage, and a name that must never be uttered.
It seemed...
I had been claimed as a Grimoire Mage of the Outer Gods.