A rhetorical question. No male or female could ever possibly refuse such a request when it came from Asahina. So it’s okay. I mean, this bed is too big for one person…(Hold on.)

She giggled and released my arm with a smile as she began to unbutton her shirt, which was already half-open to begin with, deliberately exposing soft curves that made my head spin. The same cleavage I had seen when I accidentally opened the door while Haruhi was putting Asahina into a bunny outfit, in the photographs that were slumbering in a hidden folder on the hard drive of our computer. (Wake up. You’ve got it wrong.)

Only two buttons remained fastened on her white shirt…no, make that one. This was more erotic than if she’d been completely naked. Since we were dealing with a quality model here. After all, this was Asahina. (Hey.)

Asahina looked up at me with upturned eyes as she flashed a shy and seductive smile. Her fingers lingered on the last button. I should avert my eyes. (Look closer.)

Her shirt was essentially split down the middle to reveal pale skin that rose and fell with each breath. A scene that was just as artistic as Venus on a shell (You’re doing it wrong.) with one side of her glistening bosom (That’s more like it.) adorned by a star-shaped…

I suddenly sucked in a deep breath.

“Grr…!”

I jumped away from the bed like a loaded spring.

“No!”

Take a closer look. How did I not notice? The method of verifying Asahina’s identity that I knew best. I used it just the other day. If I checked a certain spot on Asahina’s body, I would know.

“Who are you?”

—This Asahina didn’t have a mole on her left breast.

The half-naked girl looked up at me in distress.

“Why? Are you rejecting me?”

What if this was the real Asahina? (I already said that you’re wrong.) Would I still have been able to keep a firm grip on my libido? No, forget that. That wasn’t the issue here. Asahina would never sneak into my room to seduce me. She didn’t need to.

“You aren’t Asahina.”

I slowly inched backward as I stared at the tears welling up in those gorgeous eyes. Something’s wrong with me. Does it really matter if she’s Asahina or not when I’m making her look so sad? (Stop that.)

“Enough of that.”

I managed to get the words out of my mouth.

“Who are you? The person who made this mansion? Are you an alien or a slider? Why are you doing this?”

“…Kyon-kun.”

This Asahina’s voice was oozing with sorrow. She looked down and bit her lip before taking action.

“!”

Her shirt fluttered in the air as she raced for the door like the wind. She paused for a moment in the doorway and turned to me with teary eyes before dashing out into the hallway. The door slammed shut with a surprisingly loud sound that woke me up as I remembered that the door had been locked from the inside. It should have been impossible for anybody to get in without a spare key.

“Please wait!”

I yelled out in a polite voice as I ran over to the door and threw it open.

Bam. Another loud sound. I certainly used a considerable amount of force, but opening a single door shouldn’t produce that much noise—

“Huh? You…”

Haruhi’s face was right in front of mine. Haruhi, in the room across the hall, had opened her own door at the same time and stuck her head out as she stared at me with her jaw dropped.

“Kyon, weren’t you in my room a second ago…or I guess not.”

Haruhi and I weren’t the only ones sticking our heads out in the hallway.

“Um.”

Asahina, wearing a T-shirt, was to Haruhi’s right as she stuck her puzzled face through a half-open door. On the opposite side—

“…”

—was Nagato’s slim figure. I also looked to my side.

“Well, well.”

Koizumi was scratching his nose as he gave me an odd look and smiled awkwardly.

That explained the loud sound at least. The five of us had opened our doors at virtually the same time. A quintet in unison, if you will.

“What’s up with everybody?”

Haruhi was the first to recover and glare at me.

“Why did everybody come out of their room at the same time?”

I was chasing a fake Asahina—or so I was going to say when I realized that Haruhi had said something rather odd.

“What about you? Were you going to the bathroom or something?”

Surprisingly enough, Haruhi looked down at the floor and bit her lip before she finally responded.

“I had a weird dream. A dream where you snuck into my room. You were talking and, um, acting completely out of character so I knew that something was wrong…Yeah, I punched you in the face and you ran away…Huh? It was just a dream…right? But something doesn’t seem quite right.”

If that had just been a dream, it would mean you’re still dreaming at this very moment. I watched as Haruhi’s brow creased and Koizumi walked over to me.

“I had a similar experience.”

He stared at my face.

“You also appeared in my room. At least, someone who matched you perfectly in outward appearance. However, the person who resembled you was behaving in a rather uncomfortable manner…Well, let’s just say that he did some things I would never expect you to do, yes?”

I was getting scared for no real reason. I looked away from Koizumi’s smirking face and focused my attention on Asahina. The real one. I could tell instantly. How could I have been fooled by that phony? Behavior, general aura, you name it. This was how Asahina was supposed to be.

I’m not sure how Asahina interpreted my gaze, as she suddenly blushed. I was about to ask if I had also shown up in her room.

“Suzumiya came to me.”

She twisted her fingers together.

“Um, a Suzumiya that was kind of strange…I’m not sure how to say this, but she almost seemed like an imposter…”

It was an imposter. That was clear, but what was going on here exactly? Each of us had a fake member show up in our room? Asahina in my room, me in Haruhi and Koizumi’s room, Haruhi in Asahina’s room…

“Nagato,” I said before asking, “who came to your room?”

Nagato, dressed only in a T-shirt like Asahina, silently looked up at me with a seemingly numb expression on her face.

“You.”

She responded in a barely audible voice before slowly closing her eyes.

And then—

“…Yuki?!”

—Haruhi exclaimed in the background as I witnessed an unbelievable sight.

Nagato, the one and only Yuki Nagato, collapsed in a heap as if an invisible hand had pushed her down.

“What’s wrong, Yuki? Hey…”

Every one of us was left dumbstruck, with the exception of Haruhi, who immediately ran over to support Nagato’s small frame.

“Whoa…She’s burning up. Yuki, you okay? Hey, Yuki!”

Nagato’s eyes were still shut and her head was limp. Her expressionless face suggested that she was asleep. However, I had a gut feeling that Nagato wasn’t simply slumbering away.

Haruhi put her arm around Nagato’s shoulder as she started to bark out orders with a stern look on her face.

“Koizumi, carry Yuki to her bed. Kyon, go find some ice bags. There should be some around there somewhere. Mikuru, go wet a few towels.”

Asahina, Koizumi, and I stood there gaping for a moment before Haruhi yelled at us again.

“Hurry!”

 

Once I saw Koizumi lift up the unconscious Nagato, I quickly headed down the stairs. Ice bags, huh? Where am I supposed to look…

That particular line of thought was probably a sign that I hadn’t recovered from the shock of seeing Nagato collapse. I still couldn’t believe what had happened. As a result, I could no longer be bothered to care about the mystery surrounding the fake Asahina in my room or the phonies that had appeared in the other rooms. Do whatever you want. It’s got nothing to do with me.

“Balls.”

We were seriously in trouble. Damn, I’d been hoping to let Nagato enjoy a normal and peaceful life for a while, but this would be the exact opposite.

As I wandered around without any idea of where to find any ice bags, I somehow ended up in the kitchen. In my house, we kept the cooling sheets in the fridge instead of the first-aid box. Was that the case in this mansion?

“Wait.”

I froze as I was about to grab the handle of the large refrigerator. I visualized an ice bag and concentrated as hard as I could.

Then I opened the fridge.

“…Knew it.”

A blue ice bag rested on top of a head of cabbage.

How considerate of them. A very convenient mechanism. But it was having the opposite effect—that of strengthening my resolve.

That we couldn’t stay here another second.

   

I left the dining hall with the chilly ice bag in my hand when I saw Koizumi standing by the entrance to the mansion. He was staring at the door, but I wasn’t sure why. Did Haruhi order him to gather snow or something?

I walked over to offer a few words of candid advice, but Koizumi noticed me and spoke first.

“Perfect timing. Could you take a look at this?”

He pointed at the door.

I saved my own remarks for later and looked in the direction he was pointing to discover something so strange that I was left speechless.

“What is this?”

Those were the only words I could manage.

“I didn’t notice this here earlier.”

“Yes, it wasn’t here before. I was the last person to enter the mansion. I checked the door when I shut it and this wasn’t there at the time.”

An object that was difficult to describe had been attached to the inside of the front door of the mansion. I guess the closest comparison would be something along the lines of a console or panel.

A shiny metal plate—or I guess that “panel” would be the most appropriate word here—around twenty inches long on each side was affixed to the wooden door, sporting symbols and numbers that made my head hurt.

I sucked it up and focused my eyes. First, at the very top:

   

x – y = (D – 1) – z

   

And then a little below that:

   

x = □, y = □, z = □

   

The boxes were actually indentations, as if we were supposed to place something in them. I stared at the three holes in bewilderment.

“The pieces are over there.”

Koizumi pointed at the floor, where there was a wooden box with an assortment of numbered blocks inside. On closer look, there were three sets of blocks numbered 0 through 9. I picked one up. It was shaped like a mah-jongg tile and was about the same weight. However, the difference was that the surfaces of these tiles were engraved with Arabic numerals.

Blocks for the ten different digits with three of each, all stored in the flat wooden box.

“The numbers that correspond to the solution for this equation,” Koizumi said as he picked up a block and examined it, “should be placed in the open spaces, I presume.”

I looked back at the formula again. My head began to hurt. Math was one of the many subjects that gave me considerable trouble.

“Koizumi, do you know the answer?”

“I believe that I have seen a similar problem before, but I’ll need more information before I can try to solve it. If the goal is to simply make both sides of the equation equal, there are a multitude of possible combinations. But if this puzzle only has one correct solution, we will need additional conditions before we can settle on an answer.”

I turned my attention to the letter in the equation that didn’t quite fit.

“What’s with the D? It looks like we aren’t required to solve for it.”

“And it’s the only letter that’s uppercase.”

Koizumi toyed with a number 0 tile as he lowered his voice.

“This formula…I have a feeling that I recognize it. It’s on the tip of my tongue…What was it? I’m pretty sure that I saw this recently.”

He stood in place with his brow creased. That’s unusual. You rarely ever see Koizumi with a serious look on his face, deep in thought.

“So, is this supposed to mean something?”

I returned the tile in my hand to the box.

“I can see that a math problem suddenly popped up on the inside of the door, but why does it matter?”

“Yes.”

Koizumi seemed to snap out of it.

“It’s the key. The door has been locked. There is no way to open it from the inside. I spent some time fiddling with the doorknob to no avail.”

“What?”

“You’ll understand once you give it a try. As you can see, there is no keyhole or lock on the inside.”

I gave it a try. The door wouldn’t open.

“Who locked the door and how? If this is an automatic lock, we should be able to open the door from the inside.”

“More proof that common sense does not apply in this space.”

Koizumi went back to his mindless smile.

“I do not know who is responsible, but someone is trying to trap us in here. The windows have all been sealed shut and the door at the entrance is locked tight…”

“So, what about the formula on the panel? A quiz for killing time?”

“If I’m not mistaken, this formula is the key to opening the door.”

Koizumi sounded rather calm.

“Our only means of escape, provided to us by Nagato.”

 

Koizumi paid no heed to the rush of nostalgia I was experiencing after recent memories had resurfaced as he continued to rattle away.

“You could call this a war of data. A form of limited conflict, if you will. Someone has trapped us within this alternate space. Nagato has countered by providing us with a means of escape. I assume that this formula would be the result. If we solve this equation, we will be able to return to our original dimension. If we fail, we’ll be stuck here. Simple as that.”

Koizumi rapped on the door.

“We have no way of knowing the basic details of this war. As this is a war of data between elemental entities, it is beyond our understanding. However, their struggle is manifested through such practical measures. This panel would be one such example.”

A math problem didn’t seem to fit in with this bizarre mansion.

“This is no coincidence. Each of us experienced a rather peculiar dream, which was immediately followed by Nagato’s collapse and the appearance of this panel on the door…This sequence of events did not occur by accident. They must be related somehow.”

If Koizumi was worried in any way, he was doing a good job of hiding it.

“I am positive that this is the key to our escape. Most likely courtesy of Nagato.”

I checked to see if it said COPYRIGHT © BY YUKI NAGATO on the panel anywhere. It didn’t.

“This is merely conjecture, but I believe that Nagato’s power is limited in this space. Now that her link with the Data Overmind has been severed, she can only rely on her innate abilities. That would explain the haphazard means of escape.”

You’re making a lot of sense for mere conjecture.

“Yes, I suppose. The ‘Agency’ has made contact with other interfaces aside from Nagato, so I happen to have access to certain information.”

I was interested in hearing about these other aliens, but there wasn’t time for that right now. We needed to deal with this weird puzzle first. I was looking between the symbols on the panel and the numbered blocks in the wooden box when I remembered something Nagato had said in her flat voice.

“This space is putting strain on me.”

I didn’t know the identity of the person who had led us into this mansion in the middle of a blizzard, but I wasn’t going to forgive whoever was responsible for Nagato’s getting a fever and passing out. I wasn’t about to go along with that little puke’s plans. I was ready to do whatever it took to get out of this place and back to Tsuruya’s vacation home. Accompanied by every single SOS Brigade member, no exceptions.

Nagato had done her job. I couldn’t see or hear her handiwork, but I was certain that she’d been fighting this invisible “enemy” from the second we stepped into this alternate space. That was probably why she looked more out of it than usual. As a result, she was able to create this small opening as she collapsed. Now it was our turn to open the door.

“Let’s bust out of this joint.”

Koizumi responded to my proclamation with an easy smile.

“Of course, that was the plan. This place may be comfortable, but I wouldn’t want to stay here forever. Utopia and dystopia are merely two sides of the same coin.”

“Koizumi.”

My voice was so serious that I surprised myself.

“Can you use your ESP to open a hole? The situation’s looking bad. With Nagato the way she is now, you’re the only one who can do something about this.”

“You are overestimating my abilities.”

Koizumi was still smiling, despite our current predicament.

“I do not recall ever saying that I am an omnipotent esper. My powers only come into play under certain conditions. You should be aware of that fact by—”

I didn’t bother listening to the rest of his sentence. I grabbed Koizumi by the collar and pulled him over to me.

“I didn’t ask for your excuses.”

I glared at Koizumi and that cynical smile of his.

“Don’t you specialize in alternate space? Asahina can’t be depended on, and Haruhi’s out of the question. There must be something you can do, like with the cave cricket. Or is your ‘Agency’ made up of a bunch of useless losers?”

I would also be a useless loser in this case. There was nothing I could do. I couldn’t even keep my cool, which probably placed me below Koizumi. The only idea I could come up with was to beat the crap out of Koizumi, and then have him beat the crap out of me. Since I wouldn’t be able to beat the crap out of myself without holding back.

“What are you doing?”

A sharp, irritated voice stabbed into my back.

“Kyon, what’s going on with those ice bags? You were taking forever so I came down to check on you and what? You’re sparring with Koizumi? What are you trying to do?”

Haruhi was standing at full height with her hands on her hips. The look on her face reminded me of an old man in my neighborhood who managed to catch a chronic persimmon thief red-handed.

“Could you be more considerate of Yuki? There isn’t any time for you to play around!”

If Haruhi was interpreting this exchange between Koizumi and me as “playing around,” her mind was clearly elsewhere. I released my grip on Koizumi and picked up the ice bag from the spot on the floor where it had fallen while I wasn’t paying attention.

Haruhi quickly took the bag from me.

“What is this?”

Her gaze shifted to the odd equation on the door. Koizumi straightened his collar as he replied.

“Indeed, the two of us were wondering the same thing. Do you have any ideas?”

“Isn’t that Euler?”

I was thrown off by Haruhi’s instant response. Koizumi continued.

“You mean Leonhard Euler? The mathematician?”

“I don’t know his first name.”

Koizumi looked back at the puzzle panel on the door for a few seconds.

“I see.”

He snapped for dramatic effect.

“Euler’s polyhedron theorem. This must be a variation of that. Suzumiya, I am amazed that you were able to recognize this.”

“I might be wrong. But the D is probably where you put the number of dimensions. I’m guessing.”

Let’s not worry about whether you’re right or wrong. I have a much more obvious question that needs to be answered first. Who is Euler and what did he do? What is a polyhedron theorem? Did we learn about this in math? Though I was hesitant to ask all of these questions, since I was always half-asleep during math class.

“No, this usually doesn’t come up in high school math courses. However, I’m sure that you’ve heard of the Seven Bridges of Königsberg.”

That I know. That was one of the puzzles math teacher Yoshizaki mentioned during class. You have two islands connected to the mainland by a number of bridges and you have to cross all of them once and only once? I remember that there isn’t a solution.

“Yes.” Koizumi nodded. “The problem was originally formed on a flat plane, but Euler proved that it also applied to a three-dimensional plane. He formed a number of famous theorems, and this is one of them.”

Koizumi explained.

“His theorem states that when you look at a convex polyhedron and take the number of vertices plus the number of faces minus the number of edges, you will always end up with two.”

“…”

Koizumi must have recognized my desire to abandon anything related to math as he smiled wryly and slid one arm behind his back.

“Then I shall use a simple diagram to explain.”

He took out a black felt-tip pen. Where’d that come from? Had he been carrying that around on him? Or did he use the same method I had used to obtain the ice bag?

Koizumi knelt down on the floor and began to cheerfully draw on the red carpet. Neither Haruhi nor I even moved to stop him.

In this mansion drawing on the furniture, floors, or walls was clearly not a problem.

Eventually, he produced a picture of a dice-like cube.

“I’m sure that you can see this is a regular hexahedron. There are a total of eight vertices. It has six faces, as the name would tell you. And there are twelve edges. Eight plus six minus twelve equals two…yes?”

Koizumi must have felt that wasn’t enough, as he drew a new diagram.

“Now we have a square pyramid. Count and you’ll find there are five vertices, five faces, and eight edges. Five plus five minus eight will also yield an answer of two. You could apply this formula to any polyhedron up to a hectohedron with a hundred faces and the answer will always be two. This would be Euler’s polyhedron theorem.”

“I see. I understand now. But why did Haruhi mention the number of dimensions?”

“That is also quite simple. This polyhedron theorem is not limited to three-dimensional objects, as it can also apply to two-dimensional planes. However, in that case vertices plus faces minus edges will consistently yield an answer of one. This form of the theorem can be applied to the Seven Bridges of Königsberg.”

A new doodle appeared on the carpet.

“As you can see, this is a pentagram. A star that can be drawn in one stroke.”

I did the counting myself this time. There were one, two…ten vertices. It had…six faces. The number of edges would be the highest at, uh, a total of fifteen. Which would give you the equation ten plus six minus fifteen, and the answer was—one.

By the time I finished running those calculations in my head, Koizumi had finished drawing a fourth diagram. This one looked like a failed attempt at the Big Dipper.

“The theorem also applies to such irregular figures.”

I was starting to get sick of this, but I did the math anyway. Uh...seven vertices, one face, and seven edges? I see, you still get one.

Koizumi smiled brightly as he replaced the cap on the felt pen.

“In other words, the answer for a three-dimensional object will equal two and the answer for a two-dimensional plane will equal one. With that in mind, let us return to the formula before us.”

He used the pen to point to the panel on the door.

X – y = (D – 1) – z. Let us assume that x refers to the number of vertices. We can then assume that y, the variable being subtracted, is the number of edges. The z, or number of faces, is more difficult to discern, as it was shifted to the right side of the equation and consequently had its sign reversed. As for the (D – 1), the difference should equal two for a polyhedron and one for a flat plane, which means that D would be three when dealing in three dimensions and two when dealing with two dimensions. Thus, the D refers to the number of dimensions. D for ‘Dimension.’ ”

I listened to him in silence and concentrated on thinking. Yeah, I think I more or less understand now. I see. So this is the theorem thing Herr Euler came up with.

“So?”

I posed this question.

“What’s the answer to this math quiz? Which numerical blocks do we use for x, y, and z?”

“Well.”

Back came Koizumi’s answer.

“I don’t know. Not without the original polyhedron or plane as a reference.”

There’s no point, then. Where are we supposed to find the original figure?

Koizumi merely shrugged, which only added to my irritation.

However, that was when something happened.

Haruhi, who had been staring at the equation with a look of concentration on her face, abruptly remembered something else she was supposed to do.

“Forget about this—anyway, Kyon!”

She suddenly yelled at me.

“You need to visit Yuki later.”

I was going to do that anyway, but why are you being so high and mighty about it?

“Because she called out your name while she was mumbling. Only once though.”

Nagato called out my name? Mumbling?

“What did she say exactly?”

“She just went, ‘Kyon.’ ”

Nagato had never called me by that name before. Hell, I can’t recall her ever calling me by my actual name or nickname or any sort of name for that matter. She always addressed me by a second-person pronoun…

I felt this irregular haze of emotion bunch up in my chest.

“No…”

Koizumi voiced an objection.

“Are you sure that she said the word ‘Kyon’? Is it possible that you misheard her?”

What’s with him? He’s going to complain about what Nagato says in her sleep?

However, Koizumi paid me no attention as he looked straight at Haruhi.

“Suzumiya, this is very important. Please try to remember.”

Koizumi’s tone was so intense that Haruhi appeared to be surprised as her eyes wandered upward while she thought hard.

“Yes. I didn’t hear her very clearly, so it might not have been ‘Kyon.’ And her voice was soft. She could have been saying ‘hyon’ or ‘jyon.’ But I’m pretty sure that it wasn’t ‘kyan’ or ‘kyun.’ ”

“I see.”

Koizumi looked pleased.

“You’re unsure about the first syllable, but you were able to catch the last part. Aha, I see. I’m sure that Nagato wasn’t trying to say ‘Kyon’ or any of those other sounds. She meant to say ‘yon,’ I believe.”

“‘Yon’?” I asked.

“Yes, as in the Japanese word for ‘four.’ ”

“What does ‘four’ have to do with…”

I stopped in the middle of my sentence and looked back up at the formula.

“Hey.”

Haruhi’s lips were puckered together in irritation.

“We don’t have time to waste on this little math quiz. You need to worry about Yuki. Honestly!”

She swung the ice bag around as her eyes narrowed angrily.

“You better come visit her later! Got it?!”

And with that loud cry, she turned and stomped back upstairs. Koizumi watched to make sure that she was out of sight before turning to me with a look of conviction on his face.

“We have been given the required conditions. Now, we can solve for x, y, and z.”

 

“Please think back to the phenomenon we experienced a short while ago. The imposters that Suzumiya dismissed as a dream but that I found to be somewhat realistic.”

The felt pen was in Koizumi’s hand again as he knelt down.

“Let us draw a diagram that shows which apparition visited each room.”

Koizumi started by drawing a dot on the red carpet and labeling it K.

“This represents you. Asahina was the one who visited your room, I believe.”

He drew a line straight up from that point and added another dot at the end, which he labeled MA.

“Suzumiya was the one to appear in Asahina’s room.”

He drew a line from the MA point that went down diagonally to the left, and labeled the new dot HS.

“You were the one who showed up in Suzumiya’s room.”

He drew a line connecting the hs point with the K point and formed a right triangle.

“And you also appeared in my room. Though I must say that the imposter behaved nothing like you. I seriously doubt you would ever do any of those things, even if you were to go insane.”

He drew a line that went down from the K point and added a dot that was labeled IK.

“Nagato mentioned that you were also the one in her room.”

I’d already realized what he was doing. He drew a line extending from the point that represented me and labeled the new dot YN before replacing the cap on his pen to signal that he was done.

“They were all related. The imposters that were neither dream nor reality were apparitions Nagato created.”

I looked carefully at Koizumi’s newest diagram.

A figure four that could be drawn in one stroke.

“We simply need to apply this figure to the formula on the door. A relationship chart that connects us to the fakes we saw. The figure is a flat plane, so D will automatically equal two.”

He continued before I had a chance to do the math in my head.

“For this figure, the number of vertices would be the number of members, so five. There is only one face, the triangle formed by you, Suzumiya, and Asahina. There are a total of five edges.”

Koizumi brushed aside a bang and smiled.

X equals five, y equals five, z equals one. That would be the answer. Both sides happen to equal zero.”

* * *

There wasn’t any time to be impressed or offer praise.

I picked up the three corresponding numerical blocks. Now that we had established a solution, we needed to quickly apply it.

However, Koizumi apparently still had his doubts.

“I am afraid of the possibility that this is an erase program.”

I guess I might as well ask what he’s talking about.

“If we are mere copies that only exist within this simulation, there is no need for us to leave this alternate space. The originals already exist in the real world.”

Koizumi raised both arms in supplication.

“It is entirely possible that solving this equation will trigger a process that will delete our existences. In other words, we would be committing a form of suicide. Now, would you prefer to live here for an eternity in relative comfort with very little variety, or would you prefer to be deleted?”

I don’t like either option. I have no wish to live forever, but I’m also firmly against the idea of ending my life anytime soon. I am my own man. There is no substitute for me.

“I trust Nagato.”

My voice was surprisingly calm.

“I also trust you. I believe that your answer is the correct one. However, that trust is limited to your solution to this equation.”

“I see.”

I had to wonder if Koizumi had mastered the art of telepathy as he smiled gently and took a half step back.

“I shall leave the decision up to you. No matter what happens, I can follow you and Suzumiya. After all, it’s my job and my duty.”

Good thing that you seem to be enjoying yourself then. It’s hard to find a job that’s actually fun.

Koizumi’s smile became a little more serious.

“Assuming that we are able to return to ordinary space, I have a promise I would like to make.”

He almost sounded at peace.

“If a situation should ever arise where Nagato is in a great deal of trouble and that situation is beneficial to the ‘Agency,’ I will betray the ‘Agency’ one time and ally myself with you.”

Ally yourself with Nagato, not me.

“Under those circumstances, you would certainly be the first to back Nagato, so allying myself with you would be the equivalent of helping Nagato. Though my choice of wording may have been convoluted.”

One side of his mouth twitched.

“Personally, I consider Nagato to be an important fellow member. I will want to stand by Nagato’s side this one time should it be necessary. I may be a member of the ‘Agency,’ but I am first and foremost the deputy brigade chief of the SOS Brigade.”

Koizumi was giving me a rather patronizing look. A look that seemed to suggest that he was satisfied and abandoning his right to speak his mind, now that his turn was over. In that case, I won’t hesitate to do as I please.

Back in the middle of December—I’d been the only person left behind in a strange world, and after a considerable amount of running around, I’d managed to make my escape. The difference was that the rest of the SOS Brigade was here with me this time. No need for a Dragon Palace. We wouldn’t be the ones disappearing. This space would.

I placed the blocks into their appropriate slots without any hesitation.

Click. I heard a satisfying sound. The sound of something metallic being lifted.

I held my breath and grabbed the doorknob. Then I focused all my strength.

The door slowly began to move.

   

——

   

I’ve been through a number of experiences that left me making sounds that couldn’t be considered human speech. Whether it was from shock and disbelief or complete awe, there have been many times when I found myself thinking, “You’ve gotta be kidding me.” I had figured that after being churned through space and time again and again, I would have developed a resistance—like how cockroaches become immune to bug spray.

But it appears that I’ll have to strike that idea.

As soon as the heavy door finished opening—

——

—I found myself in a situation where I couldn’t make any sound.

I couldn’t believe my own eyes. Why would my optic nerves send such images to my brain? Did something go wrong? My retinas or lenses had gone out of whack or something?

The blinding sunlight made me dizzy. Bright rays of sunshine shone above.

“—The hell…”

The skies were so clear that I almost sneezed. There wasn’t a single snowflake to be seen, let alone a howling blizzard. Blue skies stretched as far as the eye could see, without a speck of cloud in sight. There were only…

Lift cables obstructing the view. I could see a couple dressed in skiwear riding the clattering lift.

I staggered, as my legs felt heavier than they should.

There was snow. I was standing in snow. The sparkling white landscape only served to make me dizzier.

I sensed someone coming and looked up to see a figure glide right past me at breakneck speed.

“Wha?!”

I jumped reflexively and followed the figure with my eyes. It was a skier who had avoided me like I was an obstacle, wearing carving skis.

“This is…”

The ski slope. No doubt about it. A casual glance immediately revealed that there were skiers all around, enjoying themselves.

I looked around. The weight I felt on my shoulders belonged to the skis and poles I was carrying. I looked down at my feet to find that I was wearing ski boots. And I was dressed in the skiwear I had been allotted when leaving the Tsuruya vacation home.

I quickly turned to look behind me.

“Ah…?”

Asahina’s mouth was open like a baby carp’s as she blinked rapidly.

“Wow.”

Koizumi was looking up at the sky in amazement. Naturally, they were both dressed in their skiwear, not T-shirts.

The mansion was nowhere to be found. In fact, it no longer existed. We were in the middle of a little-known ski slope. No sign at all of any uncharted, suspicious-looking mansions.

…Which meant…

“Yuki?!”

I heard Haruhi’s voice come from up ahead as I turned my head and eyes in a rush.

Haruhi was holding up Yuki, who had apparently been lying on the snow.

“Are you okay? Yuki, is your fever…huh?”

Haruhi glanced around the way a pika would after exiting its burrow.

“That’s odd…We were inside the mansion a moment ago.”

Then she noticed me.

“Kyon, something about this feels weird…”

I didn’t answer as I dumped my skis and poles and knelt down next to Nagato. Haruhi and Nagato were wearing the same clothes as when they’d been dashing down the slopes.

“Nagato.”

My call was met by her short hair’s rustling ever so slightly as she slowly lifted her head.

“…”

Two big eyes on a face completely void of emotion looked up at me, same as always. Nagato’s face was covered with snow as her gaze fixated on my face for a bit.

“Yuki!”

Haruhi knocked me out of the way as she grabbed onto Nagato.

“I have no idea what’s going on. But…Yuki, are you awake? Do you still have a fever?”

“No.”

Nagato responded in a flat voice as she stood up on her own.

“I merely tripped.”

“Really? But you have a terrible fever…or so I thought, but huh?”

Haruhi placed a hand against Nagato’s forehead.

“You’re right. It’s gone. But.”

She looked around our surroundings.

“Huh? The blizzard…Mansion…No way. It couldn’t have been…a dream. What? Was it…a dream?”

Don’t ask me. I don’t provide reasonable answers. Not when you’re the one asking the questions.

I feigned ignorance as I heard voices calling in the distance.

“What’s up?”

I could see two figures waving their hands from the bottom of the slope.

“Mikuru! Harls!”

It was Tsuruya. Next to her were three snowmen of different sizes, and the other figure stood next to the medium-size one, which happened to be of similar height. Jumping up and down was my sister.

I was able to reestablish our current position.

The five of us were gathered a short distance from the lift station below the beginner’s course.

“Well, whatever.”

Haruhi apparently gave up on thinking about it.

“Yuki, I’ll carry you, so get on my back.”

“I am fine,” said Nagato.

“You’re not,” Haruhi objected. “I don’t really know what happened or why I’m so confused, but I’m not going to let you overexert yourself. You don’t have a fever, but I just have a feeling that you’re unwell. You need rest!”

Haruhi didn’t wait for an answer before hoisting Nagato on her back and running off toward Tsuruya and my sister, who were still waving at us. She was probably going faster than a brand-new snowplow. Haruhi was going so fast that if there were a piggyback 100-meter dash event in the Winter Olympics, she’d be guaranteed gold.

   

Afterward.

Tsuruya contacted Arakawa, who picked us up in his car.

Nagato, in protest against Haruhi’s treating her like a sick person, attempted to convince us that she was in good health, but the looks I gave her must have had some effect, as she eventually shut up and did as Haruhi said.

Nagato, Haruhi, Asahina, and my sister got in the car to return to the vacation home first, which left Koizumi, Tsuruya, and me to walk back on foot.

During that time, I engaged in conversation with Tsuruya.

“Say, I saw you guys walking down the slope and carrying your skis. What was up with that?”

Uh, there was a blizzard?

“Hmm? Oh, there were, like, ten minutes of heavy snowfall, I guess? But it wasn’t that bad. Just a quick flurry out of nowhere, yeah?”

It appeared that we had spent hours walking around in the snow and relaxing in the mansion while only a few minutes had passed for Tsuruya.

Tsuruya continued with a brisk pace and tone.

“When I saw the five of you just scooting your way down, I was like, why? And then Nagato, leading the way, took a tumble. She got right back up, though.”

Koizumi could only smile weakly as he kept his mouth shut. I did the same. So that was how we had appeared to an outside observer, in this case Tsuruya. And that was probably correct. We had been in some kind of dream or illusory world. This was reality, the original world.

After walking along in silence for a while, Tsuruya chuckled and moved her mouth next to my ear.

“Hey, Kyon. On a different note.”

What’s up, ma’am?

“I can tell from looking that Mikuru and Nagato aren’t exactly normal. And Harls wouldn’t be considered normal either!”

I stared at Tsuruya and discovered that the cheerful look on her face was genuine.

“You noticed?”

“Long, long time ago. But I don’t know what they actually do! But they’re doing some funny stuff behind the scenes, right? Ah, keep this a secret from Mikuru. She thinks that she’s acting like an ordinary person!”

She must have found the look on my face amusing, as she doubled over and laughed heartily.

“Yep! But you’re normal, Kyon. You and I are the same in that sense.”

And then she peered at my face.

“Welp! I’m not going to ask about Mikuru’s identity! Probably hard to answer! Doesn’t really matter. We’re still friends!”

… Haruhi, forget about the junior brigade member or honorary advisor stuff. Recruit Tsuruya as an official member. She’s probably more perceptive than I am and better at playing the role of an ordinary person.

Tsuruya whacked me on the shoulder repeatedly.

“Take care of Mikuru. If she’s ever troubled by something that she can’t talk to me about, help her out!”

Well…but of course.

“Still.”

Tsuruya’s eyes were shining.

“That movie you made for the cultural festival. Was that actually based on a true story?”

I wasn’t sure if Koizumi heard her, but I could see him shrugging off to the side.

   

When we arrived back at the vacation home, Haruhi had already forced Nagato into bed.

Her pale complexion was no longer dazed like it’d been in the mansion. She now had the same cool demeanor as when she was reading in the clubroom. I could even sense microscopic shifts in emotion. The Nagato we know and love.

Asahina and Haruhi were standing next to Nagato’s bed like enchanting nurses while my sister and Shamisen were also standing by. I guess that they were waiting for us to arrive, because Haruhi began to talk once we were all assembled.

“Say, Kyon. I have a feeling that I had this strangely realistic dream. We went to a mansion, took a bath, and made some hot sandwiches to eat.”

I was about to say that she’d been hallucinating, but Haruhi continued.

“Yuki said that she didn’t know anything, but Mikuru remembered the same things I did.”

I glanced over at Asahina. The lovely tea-serving maid looked down apologetically.

This is a problem. I was hoping to convince her that she’d been hallucinating or daydreaming, but I wasn’t going to come up with a reasonable explanation for why two people had the same daydream anytime soon.

I was trying to figure out how I might trick her when I was interrupted.

“Group hypnosis.”

Koizumi gave me an exaggerated look of exasperation as he cut in.

“In fact, I also vaguely remember something similar.”

“You’re saying that you were hypnotized? And I was too?” Haruhi asked.

“This was slightly different from artificial hypnotism, but yes. Knowing you, if a person were to announce that they were going to hypnotize you, you would become skeptical and the hypnosis would most likely fail.”

“You’re probably right.”

Haruhi appeared to be lost in thought for a moment.

“However, we spent a considerable amount of time walking through the blizzard at a fixed rhythm where we could only see white snow. Are you aware of a phenomenon known as highway hypnosis? If you drive along a straight highway for an extended period of time, the evenly spaced lights can place the driver in a state of hypnosis and lull him to sleep. People often fall asleep while riding the train, and that’s attributed to the rhythmic shaking of the cars. It’s the same reasoning as when you pat a baby on its back to induce sleep.”

“Really?”

The look on Haruhi’s face suggested that she’d never heard of that before, while Koizumi nodded solemnly.

“Really.”

His voice took on a persuasive tone.

“As we made our way through the blizzard, someone must have grumbled about wishing there was a mansion we could hide out in that provided all sorts of comforts…something along those lines. After all, we were enduring extreme conditions at the time that left us in a mental state that would be susceptible to such hallucinations. You’ve heard about people wandering through the desert and seeing mirages of oases, yes?”

Damn Koizumi. He’s laying it on real thick.

“Uh-huh…I guess. So you’re saying that we experienced something similar?”

Haruhi tilted her head and looked at me.

Apparently so. I nodded in an attempt to look convinced. Koizumi saw this as the perfect time to add the finishing touches.

“The sound of Nagato falling brought us back to our senses. I’m sure of it.”

“Now that you mention it…”

Haruhi tilted her head even farther before swinging it back.

“Well, you’re probably right. It wouldn’t make sense for them to build a weird mansion out there, and my memory’s becoming hazy. Like I was dreaming within a dream.”

Yes, it was a dream. A mansion that didn’t exist in reality. An unnecessary hallucination born of fatigue.

I was more worried about the other two members. The outsiders who weren’t members of the SOS Brigade. I looked at Tsuruya.

“Heh!”

Tsuruya winked at me and smiled. I interpreted the look on her face as meaning, “Well, we’ll just leave it at that.” Though I may have been reading too much into it. Tsuruya didn’t say another word as she flashed her trademark smile and refrained from any superfluous comments.

As for the other one, my sister, she was having sweet dreams from her position leaning into Asahina’s lap. Like a cat, she was obnoxious when awake, but rather adorable when asleep. Asahina didn’t seem to mind as she watched my sister’s face. From the looks of things, I would guess that Asahina and my sister didn’t hear the latter half of Koizumi’s explanation.

Shamisen was grooming himself on the floor as he looked up at me and meowed. It was almost like he was trying to comfort me.

   

And when all was said and done, we finally reached the first night of our winter trip.

Nagato was apparently dying to get out of bed, but Haruhi would make a fuss every time by pushing her back down and throwing the covers over her.

I had a thought. There wasn’t any need to force her to sleep. Even if she were to have fun dreams, they would still only be dreams. What mattered was that we were all here together right now. It didn’t matter how wonderful a dream was if it ended the moment you woke up. I had no interest in transient illusions. This I understood—

A number of issues had been set aside. Like the identity of that mansion or whether Haruhi truly believed Koizumi’s fib. Right now she was busy playing with Nagato so she didn’t really care, it seemed.

I headed outside for no real reason, maybe to escape Haruhi’s piercing voice. The night sky was filled with more stars than you’d ever see in the city and the reflected light made for a brilliant expanse of silver. Yet for some reason, I didn’t feel cold at all.

“But.”

Tomorrow would be the last day of the year. Koizumi’s detective show would unfold on New Year’s Eve, and Haruhi was planning on partying like crazy.

In that case, we might as well relax. I doubt that Nagato had been given many opportunities to kick back. I wasn’t sure how much sleep she usually got or if she even needed to sleep, but she might as well use this chance to get her fill. Throwing Shamisen onto her bed was also a brilliant idea. He could serve as a source of heat.

I looked across the endless field of snow as I talked to myself.

“Doesn’t look like we’ll have a blizzard tonight.”

I could only hope that if Nagato was capable of dreaming, she would be granted sweet dreams on this one night.

After all, I had absolutely no reason to wish otherwise.

I also took this opportunity to pray to the stars. It wasn’t Tanabata, and it wasn’t even New Year’s Eve for that matter, but I wasn’t specifically directing this prayer to Vega or Altair. Look at all the stars out there. I’m sure that my words will reach one of them.

“Make the new year a good one.”

I’m counting on you, whoever’s out there.