The Grimoire's Pulsing Heart

The Equinox Book. The library shelves were arranged in Hangul consonant order. So where would the eighth shelf be?

The eighth consonant in Korean is 'ah'.

The first blank in the Fibonacci sequence, '8', pointed to the 'Ah' row shelf.

"Just as I thought..."

I arrived at the Ah shelf and checked the books there. They were neatly arranged in order.

There seemed to be a weird book mixed in the middle, but whatever—this was that kind of school. Best not to dwell on it.

Now I just needed to find the one corresponding to the second blank, '55'.

The eighth shelf's fifty-fifth book—so look for the one labeled 'Ah-55'.

"Fifty-fifth... fifty-fifth..."

Finally, I found it. The title of the fifty-fifth book was even more grotesque than the ones I'd just seen.

The book was bound in some unidentified dark red leather, its surface bulging like veins.

For some reason, it felt creepy even to touch, but I pulled it out anyway, held it in my hand, and flipped to the final Fibonacci blank, '233'—page 233.

"Huh?"

There was no text on page 233.

Just a single geometric diagram. No matter how I looked at it, it resembled a magic circle from the occult, and above it, in small letters, was the name of the circle.

"What the hell is this...?"

Invocation was an English word meaning prayer or incantation.

So it seemed like draw this magic circle and pray to something. This screamed black magic. In this insane world, who knew what would happen if you ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠drew a magic circle to invoke some unknown evil god.

For now, maybe call Su-hee and Jia over.

"Everyone, gather here!"

My loud voice echoed through the quiet library, making the library committee girl flinch and shrink back.

"E-eh, u-uhh."

"Ah, no, not you."

"I-in the l-library, y-you have to be q-quiet..."

She ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠must take her duties pretty seriously.

"Ah, yeah... sorry~"

As I gave the library girl a quick apology, Su-hee and Kang Jia approached.

"Ung? Oppa, were you just talking to that girl?"

"She wasn't talking to me—she was telling me to be quiet. You can't make noise in the library."

"Ah? Ung... hmm... should I kill her?"

This girl jumps straight to murder at every turn. But by now, I could tell if she was really bloodthirsty or not.

"Jeez... kill who? Come here."

Kang Jia was just whining. She meant don't talk to other girls, don't make her jealous, focus only on her—but the only way she knew to express it was "kill."

And sure enough, at the promise of a hug, she scampered over and clung to my chest so tight it hurt.

Squeeze♡

"Ehehe, hehe♡ Hooob... haaa... Oppa smells so gooood♡"

"Ahem, son~ Did you find something?"

Before Kang Jia could cling endlessly, Su-hee provided perfect backup.

-Thanks.

Nod.

Su-hee with a faint eye smile.

-Hehe. This much is basic now.

"Oppa? What're you talking about with Mom?"

Damn. Now she even picks up on eye signals between me and Su-hee.

"I was just praising how pretty my little sister Jia is. Right, Mom?"

"U-ung! Yeah!"

Su-hee shuddered, probably recalling Jia's threats from when we first entered the library—something about ripping her apart or making her infertile—and nodded vigorously.

Guess I'd have to be extra careful talking with Su-hee from now on. Can't go making innocent people barren...

"Anyway, check this out. I found it."

I briefly explained how I'd cracked the Fibonacci puzzle, then opened the Equinox Book to page 233 and showed them.

"Hoee...? Invo...cation...? What's this, Oppa? Jia doesn't get hard stuff..."

"My guess is it's some kind of occult ritual. Looks like an evil magic circle, right? In this broken world, it wouldn't be weird if this stuff was real."

"Whoa! Sounds fun! Let's do it, Oppa!"

Kang Jia bounced around innocently with zero hesitation, while Su-hee pondered.

"Mom's against it. Looks too dangerous."

I was inwardly hesitant too.

"Aww, why not~? Can't we just try it once? Pleeease?"

Kang Jia sparkled her eyes like a girl who'd found a new toy, urging us to perform the ritual.

"Jia, if the janitor or disciplinary committee shows up at school, how many could you handle?"

That was something I'd been curious about too.

"Hmm... one... three or four?"

Impressive that she could take on three or four monsters at once—things no normal human could touch. But one question.

"If your voice works on them, couldn't you handle any number?"

"Nah. It's hard for me to command a bunch at once. Makes my head hurt. I hate pain."

I see. Simultaneous activation is tough.

A weakness in Kang Jia's ability. ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠Unexpected intel.

Su-hee nodded and continued.

"What if we do this ritual and monsters you can't handle come out—or too many of them? Yuhan could get badly hurt, or worst case, lose his life."

"Gasp?"

Squeeze...

Her arms around me tightened, pulling her deeper into my chest.

"N-no! Oppa! Let's not do it. Okay?"

She was the one begging to do it, and now this...

"Yeah. Let's hold off on trying it ourselves for now. I'll take a photo and save it."

Click.

I opened the camera app on my smartphone, snapped the magic circle, and uploaded it to our group chat. I'd worried it might not show up like some ghost phenomenon, but luckily, it did.

"For now, let's research this book first, and its author, Aleister Crowley. And the Shakallu-Enshar ritual if we can."

"Yeah, let's do what Yuhan says, Jia."

"Ung! Jia will listen to Oppa."

Now she was playing the obedient little sister. Still hugged to my chest, Kang Jia looked up at me, face only.

Good little sister act—now give her a reward.

Mwah.

"Oooh♡ Heehee♡"

A light kiss on the lips, and her eyes went all dreamy as she grinned.

I gently patted her soft butt and said,

"Alright, time to investigate for real. If you find anything, come back here. Got it?"

"If Jia finds something, you'll give her a reward, right?"

"Yeah, yeah. I will."

"Wh-what if... y'know... you'll do that too?"

"Do what?"

"Uung... that thing!"

Here we go again.

"I'll do that after we escape this world. Got it?"

"Waaah... But I want it now..."

I silently stroked her back a few times.

"Fine... okay. I'll hold back then. But if Jia finds something, you gotta do it with me for sure!"

"Jeez, I got it, so go search already."

"Heehee, ung!"

What a handful.

Su-hee and Kang Jia headed off to research the author and book, while I decided to read the front pages.

Flip, flip.

The early pages were just diagrams. Magic circles made of strange languages that looked like ancient script.

"If you're gonna write a book, at least note what these do."

Impossible to make sense of. Not even what to do after drawing the circle.

If drawing this Shakallu-Enshar circle required human sacrifice or self-immolation, this run would end in a dog's death.

Flip... flip... rip!

"Ow!?"

Flipping pages irritably at the unhelpful book, my finger got cut on the paper.

"Tch..."

Whatever this paper was made of, it stung like hell. And more blood than expected.

The edge of the page had a drop of blood from my thumb smeared on it.

Gonna get an earful from the library girl again.

Thump- thump-

Then, I heard what sounded like a heartbeat from somewhere.

What?

Thump-! Thump-!

And it wasn't coming from afar. No, I wasn't hearing it with my ears—I was feeling it through my skin.

"Ugh!?"

The book's surface bulged and pulsed like a living heart.

The gross sensation, like gripping writhing flesh, made my hand go slack and drop it—but it kept twitching.

Should I pick it up again or not...?

Gulp.

My gut screamed yes.

Like peering beyond the village boundary—this run was ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠my only shot at this anomalous book. A regressor's instinct from death's return, or something else, who knows—but time to gamble.

No risk, no progress.

I picked up the book.

Thump thump thump thump

Warm. Like human skin.

Something echoed in my mind.

"!?"

What the—?