The Death Rate

The first to spot the anomaly was a newcomer in the Statistics Division. The one who continued to doubt it until the very end was Makabe Toshinori, an investigator with eighteen years of service.

Dungeon Agency, Safety Statistics Division. This was the department that compiled and categorized explorers' death and injury reports and assembled them into an annual white paper. It had no glamour. Around the agency, people secretly called it the "Condolence Division." Makabe had spent eighteen years there reading about people's deaths. He had looked through an estimated forty thousand death reports. He had written most of the current cause-of-death classification codes himself. "C-3: Death from continued combat due to delayed retreat." "D-1: Chain accident caused by a fall." "E-2: Improper knot tying." The ways explorers died had barely changed in eighteen years.

That was why he could tell when they did change.

"Makabe-san. No matter how many times I tally this, it keeps coming out like this."

The line graph the newcomer brought him showed that the death-and-injury rate among mid-level explorers—those from C-rank to B-rank—had fallen thirty percent from the same month of the previous year.

"It's a counting error," Makabe said. Eighteen years of experience made him say it. Even in years when equipment standards had been revised, this figure changed by only five percent. Thirty percent was impossible.

It took three days to confirm the impossible. No revision to equipment standards. No newly approved drugs. No discovery of a major dungeon-clearing method. Dungeon activity was actually higher than usual. Only the death-and-injury rate had fallen for no apparent reason.

Numbers always had a reason. That was Makabe's religion.

He plunged into the records of those who had not died—the mountain of survival cases and near-miss reports. On the fourth night, he came across the same group of words recurring in the free-response fields.

'I followed the retreat criteria I learned from the stream and withdrew before engaging.'

'As instructed in the course, I placed my heels first when fatigued. I did not fall.'

'Because I had practiced a quick-release knot, I was able to escape one-handed.'

A four-person C-rank party from Branch Seven had nearly been caught in a pincer attack in the middle levels, but immediately retreated according to "Shin's Course, Lesson Fourteen" and all four made it back alive. A B-rank solo explorer from Branch Two had slipped and been left hanging in midair, injuring his dominant arm—but he had untied the rope one-handed and returned under his own power. At the end of his report was this: 'Honestly, if it weren't for that course, I think I would have been recorded under E-2.'

The explorers in the field knew the classification codes he had created. And they had written that they had managed not to be counted under one.

Makabe counted. Of the previous month's survival and near-miss cases, 117 contained the word 'course' or 'Shin' in their free-response fields. The number of death cases containing either word under the same conditions was zero.

Correlation was not causation. That was also Makabe's religion. So he sacrificed his weekend and watched every archive of the course, from the first lesson to the latest, without fast-forwarding. By the time he finished, he realized that the style of the notes in his hands had changed without him noticing. They were no longer words written after death, but words meant to be passed on before death.

On Monday morning, he wrote the report.

'A Cause Analysis of the Sharp Drop in the Death-and-Injury Rate among Mid-Level Explorers.' The conclusion read: 'This course provided systematic preventive education for the first time against the three leading categories of cause of death that this agency has classified for eighteen years—delayed retreat, falls, and improper knot tying. Its content is not novel. It merely teaches before death what we have been writing after death. And until now, no one had done that.'

The section chief grimaced. "You intend to put a mere entertainment stream in an official agency document?"

"It isn't an entertainment stream," Makabe said, adjusting his glasses. "In numerical terms, this is public health. It is the same kind of phenomenon as disease rates falling after a clean-water system is put in place."

At the end of the report, he proposed creating a new classification code: 'P-1: Prevention through education.' After eighteen years of classifying nothing but death, it was the first classification the man had created for the living.

◇

"Good evening, I'm Shin. If there are any first-time viewers, let me say the usual thing. This is a course for beginners. I won't be covering flashy techniques or talking about the strongest gear. It's dull. Probably shockingly dull. —Lesson Twenty-Six: 'How to Take Breaks.'"

【Dull again today】

【That dullness saved my team and got us home last week, huh】

"To give you the conclusion first, you take a break before you get tired. A break taken after you are tired is not recovery; it's first aid. On days when you go deeper than the third level, sit down once every forty minutes even if you aren't tired. Sit down, and check your light, take your pulse, and count your remaining doses. ...Yes, those same three checks as always. We'll do it as many times as necessary. That's what fundamentals are."

After finishing the main lesson, I chose one long message that had arrived through the platform staff that day. The sender was a thirty-two-year-old male C-rank explorer. I had received his permission to read it aloud.

"Uh, one last letter. ...It starts, 'Teacher doesn't know my name or face.' I'll read it."

'Last week, I was caught in a collapse in the middle levels. Light, pulse, remaining medicine. When two of the three criteria you taught us were missing, I heard your voice in my head: "When two are missing, turn back without fighting." I didn't hesitate. Once fatigue had made it difficult to lift my feet, I walked by placing my heels first, just as you taught me. I descended the final vertical shaft with a quick-release knot. Even the colleague who laughed at your course for being "dull" went down on the rope I tied.'

【Hey】

【Is this a true story?】

【Stop the barrage. Let him read】

'Everyone made it home. Yesterday, on my daughter's birthday, I was able to say, "I'm home." Thanks to the course, I made it home alive. I wanted, more than anything, to tell you that.'

I thought I had read it all the way to the final line.

Apparently, I hadn't. I only realized after the comment section fell silent that my voice had stopped partway through.

How strange, I thought. Even on the night one of my students became the strongest in the world, I hadn't cried.

Thinking about it, this was the first time. If it was "I got stronger," I had heard that from all five of them. That was mostly a matter of their own talent. But "I made it home alive" was the first message I'd ever received about the twenty years I'd spent doing this work.

"...Sorry. Um."

I took off my glasses, then put them back on.

"...I'm glad I did this work."

That was all I could manage to say.

【Teacher...】

【Don't cry. You'll make me cry too】

【A letter that took twenty years to reach him】

【T-Teacher...! Me too! I'm alive thanks to you too...!】

【Don't cry too, Hina-chan】

"...All right. Enough with the maudlin stuff. Here's the preview for next time: 'How to Draw a Map.' Getting stranded doesn't begin when you lose your way. It begins the moment you stop keeping records."

【The map episode from the man who "only gave us a map"】

【This can only be a legend in the making】

That very night, a clip titled 'Shin-sensei Stumbles over His Words for the First Time' raced around the world. As its view count climbed, the clip's comment section began filling with one survival report after another. I made it home using the retreat criteria too. I didn't fall either. Our entire team curls its toes inside its boots before going in—.

Statistics before they became numbers had begun piling up in a place where anyone could see them.

◇

That same week, at the medical wing of Clan Genbu headquarters.

A nineteen-year-old rising ace whom the training division had been promoting as 'the next Kenjo' was in intensive care. He had delayed his decision to retreat in the middle levels, then fallen while continuing to fight. His dominant arm and ribs were injured, and full recovery would take four months. In the Dungeon Agency's classification, it was a combination of C-3 and D-1. The only reason he had not died was luck.

"There were no problems with the training curriculum. It was due to an error in his own judgment—"

The head of training couldn't finish what he was saying.

"Two last month," Togakushi Gen said. His voice was quieter than a shout. "Three the month before. This month, it's an ace candidate. ...Why is our training program nothing but accidents?"

The head of training could not answer. The answer had long since been written amid the mountain of documents piled on the chairman's desk: the complete records of that course compiled by the research team. The more he read, the more the records looked like a catalog of everything Genbu had spent eight years cutting from its own training wing.

And that night, in a corner of the internet, someone placed two graphs side by side: the steadily falling accident rate among the course's viewers, and the steadily rising accident reports from Genbu's training division.

The arrow of comparison was quietly beginning to point toward Togakushi Gen.