With one end of the passage blocked by collapsed stone, there was only one direction we could move. The path along the shallow waterway was just barely big enough for two to walk side by side. I took the lead, lighting our way with the flashlight and having Mizuho follow a few meters behind. The passage sloped slightly in the direction we proceeded in, but it continued to be straight. A draft blew from up ahead. That implied an open space was this way, but it also meant my soaked clothing would get colder and colder.
There were several rules when it came to survival situations. Most of them had been made into acronyms. (The military had many such abbreviations. I figured it was because the terminology was overly long to begin with.)
Different instructors had their own ways of imparting the same things, but the basics didn’t change. The first thing I learned was the abbreviation PRWF.
P stood for protection—to protect yourself.
R stood for rescue—to put yourself in a place where help could find you.
W was for water—to secure water.
F was food—to secure food.
In a survival situation—that is, in any circumstance where your life was at risk—anyone could panic and lose sight of what to do. So long as you recalled those initials, you’d at least know the essential priorities.
The four rules of PRWF were listed in order of priority. In other words, everything else could wait until you protected yourself. Once you secured safety, you could set up signals and such for rescue teams to find you. No matter how safe a place you managed to find, holing up there wasn’t conducive to being located.
Water was a higher priority than food, but humans could last about three days without it. Forgoing drinking for so long spelled death, but as long as you left the proper signs, the rescue team would find you before then.
Considering those tenets, how was I to approach my strange predicament?
P. First of all, staying in this waterway was dangerous. The ceiling and walls had already begun to cave in, and the earthquakes—or dungeonstorms, was it? If the shaking continued and things collapsed, we could die. Getting out of the passage was best. However, one thing making the situation more difficult was Mizuho’s presence. If it were just me, it would be fine. I’d survived in far harsher locales before. But I’d typically been alone. If anyone was with me, it would be comrades from the Regiment. This was different. Mizuho wasn’t a soldier—she was a civilian woman.
R. Prospects for rescue were not good. I didn’t know how many casualties that restroom collapse in the airport had caused, but with a big hole having opened up in the floor, they’d have to search for anyone who got caught up in it. However… If I took Mizuho’s words at face value, I wasn’t on Earth anymore. I would have loved to laugh that one off, but I’d already experienced things that defied reason. If I was to assume none of it had actually happened, then either I was on the verge of death, with my brain showing me a very odd series of images; or someone was using hallucinogens or an actress to engage in some sort of indecipherable psychological strategy against me. Perhaps British Airways’s service was so bad that I’d passed out on the flight and fled into a nightmare. What made the PRWF rules so good was that even if one of those explanations were true, I’d still be doing the same thing.
In any case, I had to conclude that no help was coming. My best hope for assistance was Mizuho. I could only guess at whether her strangely named homeland, the Support Roman Empire Post Five, conducted search and rescue operations, but simply getting closer to human settlements raised the possibility of being found.
W. We had flowing water right under us, at least. We couldn’t drink a drop of it without boiling it first, but if we could light a fire and find a container, that would resolve the problem.
F. This, too, I’d leave for later. We could survive for three weeks without food, and it was better for our stomachs to be growling than to carelessly eat any strange poisonous bugs or mushrooms.
My on-hand gear was less than unreliable. The rucksack only had a few possessions in it, and I’d lost it during the restroom collapse. My smartphone was gone, too. That one really hurt—even if it had fallen into the water and been rendered unusable, I probably still could have taken it apart and used the pieces for something. Losing that lithium-ion battery stung.
My wristwatch was intact. The G-SHOCK’s hands pointed to three PM. It felt unreal—it hadn’t even been an hour since I’d been sitting in the airport’s food court eating my tsukimi tempura soba.
The one bit of fortune in all this was that I’d been clutching my flashlight during the quake. In this dark environment, the illumination coming from the SureFire was reassuring.
Mizuho called this place “Million Dungeon” and implied we were in a single, massive structure. The worn-down stone passage reminded me of ruins I’d seen in North Africa and Cambodia. In any case, I wanted to get out of this building soon and assess my surroundings.
As we moved, I noticed the distance between my footsteps and those behind me had widened. I turned around to find Mizuho lagging behind. She was looking down, rubbing her arms as she walked, so I stopped and waited.
“How are you doing?”
“The…the wind, it’s…colder than before.”
Mizuho was right. The air blowing past us was steadily growing harsher. For one with such a delicate frame, it had to be awful.
“Mizuho, that means we’re nearing an open area. Just a little farther.”
“Yes… All right.”
Her voice trembled. She couldn’t take much more of this.
Hypothermia might not sound threatening, but it was extremely dangerous. Even the world’s greatest soldiers would fall dead if their body temperature dropped too low. A person’s core temperature needed to be maintained in a very tight window of around thirty-seven degrees Celsius. A drop of two degrees caused hypothermia.
Plus, water drained body heat fifty times faster than air. That meant the key to avoiding hypothermia was not getting wet, but we’d long since blundered on that front.
I removed my jacket, wrung it out as much as possible, and handed it to Mizuho.