CHAPTER ONE

UNDERWORLD, MARCH 378 HE

1

The air had a certain scent.

That was the first thing I noticed, through the fragmented thoughts I had just before awakening.

The air coming into my nostrils brought a wealth of information. The smell of sweet flowers. The smell of fresh grass. The bracing, cleansing smell of trees. The tempting smell of water to a parched throat.

Next I focused on my hearing and was overwhelmed by an instant deluge of sound: The rustling of countless leaves. The cheerful twittering of songbirds. The soft hum of insect wings. The distant trickling of a creek.

Where was I? Certainly not in my home. There were none of the usual features of waking there, like the sunny smell of dried sheets, the AC’s dehumidifier’s growl, or the distant traffic over on the Kawagoe Bypass. Plus, the shifting patterns of green light on my eyelids weren’t coming from the reading light I forgot to turn off, but from the shade of branches.

I pushed aside the lingering temptation of sleep and opened my eyes.

Countless bits of light leaped into my sight, and I blinked rapidly. I had to lift the back of my hand to rub at the welling tears, and I sat up.

“…Where am I…?” I wondered.

The first thing I saw was clumps of light-green grass. Little white and yellow flowers appeared here and there, and brilliant pale-blue butterflies wandered among them. The carpet of grass ended just fifteen feet ahead, replaced by a thick forest of gnarled, decades-old trees.

I squinted into the gloom among the trunks, but as far as the light allowed me to see, the trees continued. The flowing, textured bark and ground were covered in thick moss that shone golden-green where the sunlight caught it.

Next I glanced to the right, then rotated my entire body. The ancient trees greeted me in every direction. Apparently I had fallen asleep in a little grassy opening in the middle of the forest. Lastly, I looked up and saw, among the reaching branches all around, blue sky and trails of white.

“Where…am I?” I wondered aloud again. No one answered.

No matter how hard I tried to remember, I had no memory of coming to a place like this and taking a nap. Was it sleepwalking? Amnesia? I shook my head to dispel the disturbing possibilities.

My name was Kazuto Kirigaya. Age seventeen and eight months. Living in Kawagoe in Saitama Prefecture with my mother and sister.

The easy recollection of that personal data brought me some relief, so I reached for more.

I was in my second year of high school. But I would reach the credits necessary to graduate in the first semester of next year, so I was preparing to move on to college that fall. In fact, I had been talking with someone about that. The last Monday of June—it had been raining. After class, I went to Agil’s Dicey Café in the Okachimachi neighborhood to talk with my friend Sinon—Shino Asada—about Gun Gale Online.

After that, Asuna Yuuki met up with us and the three chatted for a while, then left the café.

“Asuna…”

I spoke the name of my girlfriend, the partner in whom I placed all my trust when my back needed watching. But the memory of her face and figure was nowhere to be seen here. There was no one at all on the grassy enclosure or among the trees.

Struck by a sudden loneliness, I continued my recollection.

Asuna and I said good-bye to Sinon and got on a train. We took the Ginza Line subway to Shibuya, then got on the Setagaya Line that would take us to Asuna’s neighborhood.

When we got off, the rain had stopped. We walked down the brick sidewalk, talking about college. I revealed that I was thinking of going to school in America and made a desperate plea for her to join me. She showed me that usual smile, brimming with gentle love. And then…

The memories ended there.

I couldn’t remember what Asuna had answered, how we had separated, if I’d gone back to the station, what time I’d gotten home, or how many hours of sleep I had gotten—nothing.

Somewhat stunned by this realization, I tried desperately to summon the memory.

But Asuna’s smile merely blotted away, as if being submerged in water, and no matter how hard I tried, I couldn’t draw out the next part of the scene. I clenched my eyes shut and dug as hard as I could into that heavy gray void.

Blinking red light.

A maddening shortness of breath.

Those were the only two images I could surface, meager as they were. I sucked in a lungful of sweet air instead. The thirsty dryness in my throat resurfaced, stronger than before.

I was certain of it. I had been in Miyasaka of Setagaya Ward just last night. So what brought me here to sleep in this mysterious forest, all alone?

But was it really yesterday? The breeze playing on my skin felt nice. There was none of the humid misery of late June here in this forest. This time, a true thrill of horror ran down my back.

Were the “memories from yesterday” actually real? I was clinging to them as if to a life raft in the open sea, after a storm. Was I really me…?

I rubbed my face all over, pulled my hair, then lowered my hands to stare at them closely. As I remembered, there was a little mole near the base of my right thumb and a childhood scar on the back of my left middle finger. This brought me some amount of relief.

At that point, I belatedly realized that I was wearing an odd outfit.

It wasn’t the T-shirt I used as nightwear, or my school uniform, or any of my personal clothes. In fact, they didn’t look like any kind of clothes you would buy at the store.

My top was a half-sleeve shirt of crude cotton or linen, dyed pale blue. The consistency was uneven and rough. The sewing along the sleeve was clearly done by hand, not a machine. There was no collar, just a V-cut in the front, tied with a brown string. By touching it, I could tell that the string was not corded fabric but a piece of finely cut leather.

My trousers were the same material as the top, but an unbleached cream color. There were no pockets, and the leather belt around my waist was fastened not with a metal buckle but with a long, thin wood button. My shoes were also hand-sewn leather, and the thick leather sole was studded with a few cleats for slip resistance.

I’d never seen clothes or shoes like these before. In real life, at least.

“…Oh, okay,” I muttered, exhaling.

They were otherworldly clothes and yet quite familiar as well. They were Middle Ages European garments—in short, “fantasy” wear: a tunic, cotton pants, and leather shoes. This wasn’t the real world but a fantasy one. Just another virtual realm.

“What the hell…”

I craned my neck again. I had fallen asleep while in a full dive? But why couldn’t I remember what game I had logged in to and when?

In any case, I’d find out by logging out. I waved my right hand.

A few seconds passed, and no window appeared. I tried with the left hand instead. No results.

With the ceaseless rustling of leaves and chirping of birds in my ears, I did my best to dispel the growing prickle rising up my midsection.

This was a virtual world. It had to be. But it certainly wasn’t familiar Alfheim. In fact, it couldn’t be any of the AmuSphere’s VR worlds fashioned from the Seed engine.

Actually, I had just moments ago confirmed the moles and scars of my real body. I didn’t know of any VR games that re-created the body to such a degree of detail.

“Command. Log out,” I ordered without much hope. There was no response. Sitting cross-legged, I examined my hands once again.

There were fine swirls on my fingertips. Wrinkles on the skin of my joints. Fine body hair. Little droplets of cold sweat seeping forth.

I brushed them aside with my tunic, then examined the fabric again. The rough thread was primitively sewn into the cloth. Even the fraying of the textile into little puffs was clearly visible.

Any machine that could generate a virtual world this detailed had to be frighteningly powerful. I gazed forward into the trees and swung my arm to snatch up a blade of grass and bring it before my eyes.

The detail-focusing system that all Seed-based VR worlds used would be unable to handle that sudden action, creating a brief lag before the fine texture on the grass could load. But the very instant my eyes caught the blade, they made out fine veins, jagged edges, even a droplet of moisture hanging from the torn end.

That meant that every visible object here was being consistently generated down to the millimeter in real time. This blade of grass alone had to represent a few dozen megabytes of data. Was that even possible?

I had to stifle that line of thought before I followed it any further. Instead, I parted the grass between my feet and used my hand to shovel through the dirt.

The damp soil was surprisingly soft, and featured the occasional tangle of fine roots. I spotted something wriggling through the lattice and picked it out.

It was a little earthworm, maybe a tenth of an inch long. It writhed desperately in its dangerous new surroundings, gleaming and green. I wondered if it was a new species, and abruptly the end that appeared to be its head split open to emit a tiny screech. I put it back in the soil, feeling dizzy, and pushed the dirt back over the hole. My palm was black with dirt, and I could make out the individual grains under my nails.

After most of a minute sitting in stunned silence, I reluctantly formulated three theories to explain my circumstances.

First was the possibility of a virtual world that was an extension of today’s full-dive tech. After all, waking up alone in a forest was a stereotypical opening scene for any fantasy RPG.

But as far as I knew, there was no supercomputer capable of generating such a vibrant wealth of ultra-detailed 3-D scenery. That would mean that in the time I had blanked out, years—perhaps decades—had passed in real time.

Next was the possibility that this was a place in the real world. I was the target of some crime, or illegal experiment, or vicious prank, dressed in these strange clothes and taken somewhere unfamiliar—perhaps Hokkaido or the southern hemisphere—and released in a forest. But I didn’t think there were any metallic-green worms that screeched in Japan, and I hadn’t heard of any such thing elsewhere in the world.

Lastly was the possibility that this was a true alternate dimension, alternate world, or life after death. It was a common trope in manga, books, and anime. Dramaturgy suggested that I would soon rescue a girl being attacked by monsters, fulfill the village elder’s requests, and eventually rise as the hero to vanquish the dreaded sorcerer lord. Yet I didn’t see that rudimentary bronze sword I was supposed to start with.

I just barely overcame a sudden urge to belly-laugh and naturally ruled out the third option. If I lost sight of the boundary between reality and unreality, I would truly be losing my grip on sanity.

That left two possibilities: the virtual world or the real world.

If it was the former, no matter how ultrarealistic, there would be ways to identify this. Just climb the nearest tree to the top, then jump off headfirst. If you logged out or were revived at the nearest holy temple at a save point, it was VR.

But if this was the real world, that test would have disastrous consequences. In a suspense novel I read years ago, a criminal organization decided to put together a video of a real game of death by kidnapping ten or so people, taking them into the remote wilderness, and forcing them to kill one another for survival. It was hard to imagine that happening in real life, but then again, the SAO Incident was just about as unlikely. If this was a game taking place in the real world, committing suicide right at the beginning was a poor choice.

“In that sense, the other one was better…” I muttered aloud without realizing it. At least in Akihiko Kayaba’s game, he had done us the courtesy of appearing at the start for a detailed explanation.

I stared up at the sky through the branches and called out, “Hey, GM! Say something if you can hear me!!”

But there was no enormous face that appeared in the sky or hooded figure that popped into existence next to me. Just in case, I searched again over the little grassy opening and all over my outfit, but I found nothing that might be a rule book.

Whoever had thrown me into this place wasn’t going to answer any calls for help. Assuming the current situation wasn’t the result of some accident, at least.

With the oblivious twittering of the birds in my ears, I dedicated my mind to considering my next actions.

If this was all a real-world accident, then rushing around too much probably wasn’t a good idea. There could be rescue crews heading for my location as I sat here.

But that raised the question: What kind of accident could produce this baffling situation?

If you had to come up with whatever seemed the least unlikely, I could have been on a vacation or traveling in a vehicle—airplane or car—that suffered some malfunction, throwing me into this forest, knocking me out, and jarring my memory. It wasn’t that far-fetched—if not for the strange clothes I was wearing and the lack of any scrapes or bruises.

Perhaps it was an accident with a full dive. Some trouble arose with the transmission route, and I logged in to a place I shouldn’t be. But again, that failed to explain the tremendous fidelity of the simulation.

It seemed more and more likely that someone had designed this situation for me. In which case, I had to assume that nothing would change unless I took some kind of action.

“In either case…”

Somehow I had to find out whether this was the real world or a virtual world.

There had to be some way. It was often said that a nearly perfect VR world was indistinguishable from reality, but I didn’t believe it was possible for absolutely every aspect of the real world to be represented in perfect accuracy.

For nearly five minutes, I sat among the short grass, pondering the possibilities. But ultimately, I did not come up with a simple idea that I could test on the spot. If I had a microscope, I could examine the soil for bacteria. If I had a plane, I could try flying to the ends of the earth. But with only my own two hands and feet, the best I could do at the moment was dig in the dirt.

If only Asuna were here, she could tell me some simple, unexpected way to ascertain the nature of the world, I lamented. Either that or she would get me off my butt and taking action.

Loneliness set in again, and I bit my lip.

I was paradoxically both surprised and unsurprised by how helpless I felt, not being able to contact Asuna. Nearly every decision I had made in the last two years was made through discussion with her. Without her thought process to guide me, I was like a CPU missing half of its cores.

As far as I knew, I had been talking with her for hours at Agil’s place just yesterday. If I’d known this was going to happen, I wouldn’t have wasted my breath on Rath and the STL but asked her about ways to distinguish the real world from a highly detailed virtual…

“Oh…”

I leaped to my feet. The sound of the clearing grew faint.

What in the world? I have to be crazy not to have thought of that until just now.

Of course I knew. I was quite familiar with the technology to create a VR world that far surpassed what was available today, a type of “super-reality.” Which meant this world had to be…

“Inside the Soul Translator…? Is this the Underworld?”

No one responded, of course, but I barely registered the lack of an answer as I stared around, dumbfounded.

Knotted, ancient trees, indistinguishable from the real thing. Waving grasses. Fluttering butterflies.

“So this…is the artificial dream it wrote into my fluctlight…”

On the very first day of my stint with Rath, I got an explanation (more like bragging) about the rough working of the STL and the realness of its world from research/operator Takeru Higa.

On my first test dive, I realized that his words were not hyperbole in the least—and all I saw was a single room. While the desk, chair, and various items were all indistinguishable from reality, the space itself was much too small to be considered a “world.”

But the size of the forest around me now had to be miles wide in terms of real-world scale. In fact, if the faint outline of mountains in the far distance were real, then it was tens, hundreds of miles in scope.

You’d have to scour together all the data space in the entire Internet to create and run such an environment using existing technology. It would have to be an entirely new form of tech…something possible only through the STL’s pneumonic visuals system—but even I’d never imagined that it would be like this.

And if my supposition that this was the Underworld, the STL’s virtual realm, was correct, then it would be essentially impossible to confirm that through any kind of user action from within.

After all, every object I could see was no different from the real thing, as far as my consciousness perceived it. If I pulled out every blade of grass, my fluctlight would receive the exact same information as if I did that action in real life. Discerning the difference from real life was fundamentally impossible.

If the STL was ever going to be put to a functional use, it would definitely need some kind of notable marker that identified its VR world as such, I noted to myself as I got up to my feet.

So I didn’t have any certain proof yet, but it was reasonable to assume for now that I was in the Underworld. Meaning that in the real world, my body was lying in the STL test unit in Rath’s Roppongi lab, making two thousand yen an hour.

“But wait…is that right?” I wondered, after my momentary period of relief.

I could have sworn that Higa had told me my memories as Kazuto Kirigaya were blocked during testing to prevent data contamination. But the only part of my memory that was blank was the single day between seeing Asuna off and then getting into Rath’s STL. That was too narrow to qualify as a memory block.

Plus—yes, that was right! I’d decided not to visit Rath for a while so I could study for my finals. Sure, the pay was tempting, but I didn’t want to think that it would take only a single day for me to break a promise to Asuna.

So if this was an STL test dive, I had to assume that some issue had arisen. I looked up at the sky through the branches and shouted, “Mr. Higa! If you’re monitoring this test, call off the dive for a bit! I think there’s a problem!”

More than ten seconds passed.

Countless leaves shook in the breeze beneath the pleasant sun. Butterflies flapped their wings sleepily. Nothing changed.

“Man…I don’t know about this…”

A possibility suddenly occurred to me. Was this situation actually a test I’d elected to undertake?

Perhaps they’d blocked only the brief bit of memory before the dive and tossed me into the STL’s ultrarealistic world to collect data on what a person would do if he wasn’t able to discern if his setting was the real world or a virtual one.

If that was true, I wanted to smack my head for agreeing to such an unpleasant experiment. If I had assumed that I would easily escape my predicament through quick thinking and action, then it was a breathtakingly thoughtless decision.

I used my fingers to list a number of possibilities that explained my situation, along with totally arbitrary percentages.

“Let’s see…Chances that this is somewhere in the real world: three percent. Chances that this is an existing type of VR world: seven percent. Chances that this is a voluntary STL test dive: twenty percent. Chances that there was a spontaneous accident during the dive: 69.9999 percent. Which means…”

There’s a 0.0001 chance I got summoned to a real alternate world, I added mentally. Racking my brain for an answer wasn’t going to get me much further. If I wanted to be more certain, I had to brave danger to interact with another person, be it game player or test diver.

It was time for action.

The first step was to quench my thirst, which was reaching persistent levels. I did a full 360-degree turn in the middle of the grass. The sound of flowing water was coming from what I estimated to be east, based on the position of the sun.

Before I started off, I reached behind my back just in case, but there was no sword or even a stick there, of course. I strode forward before I could start to feel lonely about that, and in less than ten steps, I was out of the grass. Two huge trees stood at my sides like natural gateposts, and I headed through them into the dim forest.

It was mysterious and eerie within the woods, with their velvety carpet of moss underfoot. The canopy of leaves far above blocked out nearly all the sunlight, so only the rare tendril of golden light reached the ground. The butterflies of the grass clearing were replaced with strange insects somewhere between dragonflies and moths that hovered and slid through the air in silence. Occasionally I heard the cry of some unfamiliar creature. It wasn’t like any place I knew on Earth.

I walked for fifteen minutes, praying all the while that I didn’t run into any large, hostile animals or monsters. Relief set in when an array of ample sunlight appeared in the distance ahead. Based on the increased volume of sound, I could tell there was a river nearby. My thirst spurred my legs into a quicker pace.

At the edge of the thick forest, there was a ten-foot buffer of grass, followed by the reflective silver of a water surface.

“W-waddah,” I moaned piteously, crossing the final distance to the riverside and its soft undergrass. “Whoa,” I grunted as I stared into the water at point-blank range on hands and knees.

It was beautiful. The river was not very wide, but the water in its gentle curve was stunningly clear. It was absolutely colorless but for a drop of blue, the white sand of the riverbed clearly visible through the pure mountain water.

Given that, just a few seconds ago, I had been leaving room for the faint possibility that this was the real world, it might be dangerous to drink unfiltered natural water. But I could not resist the allure of a stream that looked like melted crystal in its pristine beauty. I gasped at the cutting chill of the water against my hand, but it did not stop me from scooping it up to my mouth.

It was practically nectar. The taste of such sweet, fresh, pure water made me never want to spend money on a bottle of mineral water at the store again. I scooped up the water over and over with both hands, until eventually I just lowered my mouth to drink directly from the stream.

With the intoxication of that life-water running through my veins, I finally eliminated from my mind the possibility that this was a standard full-dive VR world.

No existing unit, such as the AmuSphere, could model liquid perfectly. Polygons were just a set of coordinates connected by a plane and not well suited to depict the complex, random shifting of water. Yet the water that rippled and spilled over my hands was utterly natural in appearance.

It was tempting to dispel the notion that this was taking place in the real world, too. I sat up at last and surveyed the area. The beautiful stream; the fantastical forest that continued past the far bank; the odd, colorful fauna of the woods—none of it seemed to match up with a real-world location. After all, wasn’t it true that the more untouched by human hands a place was, the more severe it was likely to be? How could I be walking around in this light clothing and not have been bitten by any bugs yet?

Thinking about that last question seemed likely to prompt the STL into summoning a cloud of poisonous insects, so I pushed it from my mind and got to my feet. I rounded down the likelihood of a real-world location to just 1 percent and looked around.

The river flowed from north to south, curving gently. Both ends visible from here vanished among the massive trees. But based on the state and temperature of the water, I felt certain that I had to be close to the source. I’d be more likely to find civilization following the river south.

I had just set off downriver, thinking it would be a much easier trip with a boat to ride, when the breeze shifted slightly, bringing a strange sound to my ears.

It was the sound of something large and tough being struck by something even harder. Not just once. It was happening at a steady pace of about once every four seconds.

It couldn’t be an animal or a natural occurrence. It was a virtual certainty that a human was producing this noise. I imagined someone chopping down a tree, perhaps. Briefly, I wondered if it would be dangerous to approach them, then smirked at myself. This wasn’t a kill-and-steal PvP MMORPG. My best option was clearly to make contact and gain information.

I turned around and headed back upstream in the direction of the sound.

Suddenly, I experienced a brief, strange vision.

A glittering river on the right. A deep forest on the left. Straight ahead, a green path advancing with no end in sight.

Three children walked down it abreast. A boy with black hair, another boy with flaxen blond hair, and between them, a girl wearing a straw hat with flowing golden locks. They threw off dazzling light from the setting summer sun.

Is this…a memory?

Long-distant days that would never return. Days he’d believed would continue forever, that he swore to protect and cherish, but that vanished as easily as ice left in the open sun…

Those nostalgic, heady days.