chapter 37
The End of Spring (2)
Izumi, Cedric, and I arrived in front of a round-shaped hole.
But Cedric’s expression looked strange.
“…Saint, are you truly going in there? It’s filthy.”
“Filthy? What do you mean?”
“Well… that is… in any case, it’s dirty. It doesn’t suit you, Saint.”
“What? What are you talking about?”
I blinked at him in confusion.
“…Isn’t it a demon’s… waste outlet?”
“It’s still a plant, you know.”
I replied calmly.
“What do you think a tree’s waste is?”
“…What is it?”
“Tree sap or honey!”
Cedric looked utterly shocked.
So did Izumi.
“You’re saying poop is honey? That’s thesis-worthy! But wait—if the waste is liquid, wouldn’t that make it urine?”
“In the Celestial Realm, they have cloacas.”
“Ohh! That’s fascinating. But how do you know that, Saint?”
…Because I saw it on the original author’s social media.
“…Just get in already.”
“Wha—?!”
Cedric, who had been staring at Izumi with a look of disgust, couldn’t bring himself to say it to me, so instead he just kicked Izumi into the hole.
Headfirst into the slightly open hole, Izumi shouted from inside,
“It really does smell sweet!”
Still holding me, Cedric looked torn, glancing between the disgusting-looking hole and me—as if deciding which of us should go in first.
Luckily, his dilemma didn’t last long. Izumi had sliced the narrow hole wide open with his sword.
“I’ll go in.”
He stepped into the now-wide entrance—big enough for two or three people to pass through. Inside, enormous tube-like structures came into view, looking like the cross-section of a cut tree trunk.
“It really is the inside of a tree.”
“Which tube should we climb?”
The two of them looked around.
“Hero, Cedric, if you see anything—anything at all—tell me.”
“If it’s something visible… Oh! There’s something carved here.”
He ran his hand over an engraved marking and read it aloud.
“1533441542. A number?”
“There’s another number over here.”
Adjusting his hold on me, Cedric spoke.
“These numbers seem to be some kind of signposts, but I can’t make out their meaning. There must be over a hundred of these tubes.”
I know. I can see them.
‘But this is unexpected.’
In the original story, getting to the center from the entrance was easy, but here, while getting in is easy, the way forward seems full of branches and choices.
I listened to them while carefully examining the numbers engraved on each tube.
115533441542
23114413154254
53543115329
3523313415324
43343444
35233134153223
535431153252
131533441542
433434447
35233134153289
…
An endless parade of numbers!
Normally, you might groan and clutch your head, but I’ve been wrestling with numbers for over 20 years as a grad student.
I can do this.
I can… do this…
I… can… right?
‘Damn. What is this?’
Each number sequence was long, and there were repeating digits.
‘Most of the counts are even… but there are some odd ones mixed in.’
Wait a second.
I think I know this.
“Saint?”
“Have you figured something out?”
When in doubt, just try it.
After about a minute of mental calculations, I smiled in satisfaction.
“This is the Polybius cipher.”
“…Polybius cipher?”
“Poly… what?”
Izumi looked uncertain, Cedric just blank.
I explained for them.
“The Polybius cipher is a substitution cipher that uses a 5×5 grid. It’s very versatile since it can be applied to most alphabets.”
To be precise, it was invented by the Greek historian Polybius for the Greek alphabet, but in modern times it’s adapted to use with the Latin alphabet.
If you’re wondering why something like this exists in a fantasy world… the original author is Japanese! Of course there’d be traces of Earth.
“You arrange numbers 1 through 5 both vertically and horizontally, fill the grid with letters in order, and then to encode you write the row number and column number for each letter. To decode, you reverse it. It’s simple enough for children… hmm.”
Cedric’s eyes were spinning. I figured a drawing would be better.
“Hero, can I borrow your dagger?”
“Here!”
With Izumi’s dagger in hand, I carved a table into the wooden wall.
“It looks like this.”
“Oh! I remember now!”
“…I see. I understand.”
“Using this table, the numbers you read earlier can be decoded like this.”
I laid out the numbers and their words:
1533441542 → ENTER
23114413154254 → HATCHERY
5354311532 → XYLEM
352331341532 → PHLOEM
43343444 → ROOT
…
“XYLEM and PHLOEM, ROOT—those are plant structures. The numbers following them must be identifiers. That’s also why there are digits higher than 5 or odd-numbered sequences that don’t match the cipher’s even-number rule.”
The Polybius cipher uses only numbers 1–5, and each letter’s code is always two digits—so words have an even number of digits.
If those trailing numbers hadn’t been there, I would’ve figured it out faster.
“So where do we need to go…?”
“Here.”
131533441542 → CENTER.
“Let’s head for the center.”
With my confident declaration, the three of us began climbing the tubes.
When Lilliana opened her eyes, what greeted her was a reality as cruel as her dream.
No—maybe not as cruel. At least in this world, her mother and the Saint were still alive.
‘…But this is bad.’
She was certain she’d been at Deold’s side, helping him resolve an incident. But now—
“A giant tree…”
The sky was filled with clouds and branches, the sun blotted out so completely it looked like night. Under that black sky, her precious kingdom’s citizens lay collapsed.
“Lilliana!”
“Deold?”
Turning around, she saw Deold wiping cold sweat from his brow.
“It’s been like this for an hour now. Or rather… I can’t even tell when it started.”
“You had a dream too?”
“Yeah. I woke up an hour ago.”
Lilliana wondered what sort of dream Deold had. But idle curiosity could wait—fixing the current situation was far more urgent.
“Where’s the Hero?”
“I went to where he should have been earlier, but no one was there. Looks like he woke up first and went off somewhere.”
“…I see. So he wasn’t chosen to wield the Holy Sword by luck alone.”
Ignorant nobles might gossip about his lowborn origins, but there was no way the god of the main temple would choose an ordinary man.
“First, we should check near that huge tree. You can stay here, Lilliana.”
“What’s that supposed to mean?”
Her eyebrow twitched.
“I’m royalty of this kingdom. It’s against my principles to stand by when my people are in danger.”
“…Fair enough.”
Deold nodded.
Lilliana might have no magical talent whatsoever, but she’d trained in self-defense for years. She could at least protect herself.
“Then let’s—”
Before he could finish—
“Mooooo!”
“Aaagh!”
A passing minotaur slammed into Deold, sending him flying high into the air.
It was truly Deold’s day of misfortune.
