My Parallel-World Self, Under the Same Roof

"No, no, no, hold on a second."

I looked back and forth between the house and its nameplate, not just once but over and over. Tsukino-san was doing the exact same thing.

"Tsukino-san, you don't have the wrong house, do you?"

"You wouldn't mistake your own house, would you? Okay, I'm starting to lose confidence, but… yeah. This is definitely my house."

The two of us looked up at the ordinary detached house. Judging by the houses on either side and the one across the street, it couldn't be anything but my home.

So… what were we supposed to do about this?

Barging into a house that Tsukino-san was claiming as her own was a pretty high bar to clear. But this was supposed to be my house. Then again, I was losing a fair amount of confidence in that, too.

Just as I was running out of ideas, the door abruptly opened.

"What are you two doing?"

The one who poked her head out was my mom.

"Honestly. You messaged ahead, sure, but this is a little too late."

She made a slightly sulky face. A round face that looked nothing like my own mean-eyed one, a faintly childish way of carrying herself that left her age hard to pin down: my mom, exactly as I knew her.

"And you, Tsukino-chan, you're too slo-o-ow. Even with Asahi along. This boy's got an unreliable streak, after all… And we're looking after a precious only daughter here, you know. So do be careful."

Even while cautioning Tsukino-san, she was all smiles.

"I'll heat up dinner, so hurry inside."

With that parting line, Mom went back into the house.

Neither of us said anything, but I could tell we were both sorting out our thoughts. Still half-doubting, I opened my mouth.

"This is my house… isn't it? This whole vibe."

"Going by what she just said, I'm boarding at this house?"

I noticed that the way we crossed our arms and thought it over was identical.

"Just to check. Tsukino-san, is there some reason you're supposed to start living here with us as of today?"

"I don't remember anything like that, though…"

Of course, I'd never heard of it either.

If it were one of Mom's jokes, it was way too out of nowhere. And she isn't the type for that kind of humor to begin with.

For now, since it seemed settled that this was my house, at least I could go home. But I couldn't just leave Tsukino-san standing there, with no idea how to take what my mom had said.

"You want to come in for now?"

It was the kind of thing I could never normally say to a girl. Well, it couldn't be helped. If this was Mom cracking some out-of-character joke, then she was the guilty party here.

"Then, um, yeah. Sorry to intrude… I guess?"

Tsukino-san's brows drew down, troubled. Her gaze, which ought to have been sharp, took on something fragile when she glanced up at me.

She was tall for a girl, but even so she was a little shorter than me. I only noticed that now, of all times.

 

*

 

Tsukino-san, whom I'd met just a little over two hours ago, was in my room.

Seeing her plopped down in my utterly ordinary room, just a desk, a bookshelf, and a bed, was hard to wrap my head around, but facts were facts.

"Ah, sorry. I should've grabbed a cushion or something."

"No, don't worry about it."

Tsukino-san looked around the room. Had I left anything weird lying out? Once the thought occurred to me, I couldn't relax.

But now wasn't the time for that.

"So, I just went and casually talked to my mom."

Slipping it in offhandedly, so it wouldn't seem unnatural, while she was busy making dinner. High difficulty.

"Apparently you're the daughter of my dad's best friend, and because of your family's work, we're putting you up for a while."

"That's, how do I put it… it's 'Blue Box,' isn't it."

"That's exactly it, except I don't remember our lives ever being 'Blue Box.'"

"Yeah. Because this house is supposed to be where I live. Hmm."

Tsukino-san let out a small groan and cocked her head.

She stood and took another look around the room, then started wandering through it.

"My room was Asahi-kun's room."

"You mean we've got the same stuff in it?"

"No, I mean the location of the room. The furniture layout is definitely similar, and the things in it are pretty similar too… if anything, they feel almost identical. But the little details are different? Oh."

Eyes going wide, Tsukino-san reached out toward the bookshelf.

"This book. It's the reason for my bad-end kink."

Of course I recognized the plainly bound book she pulled out.

"Ah, sorry for just grabbing it. This is a literature club magazine."

"It's the Himurogioka High lit club's magazine, right? A pretty old one. I got mine back in middle school, when I went to their culture festival."

"Me too. There's a novel in it called 'Morning of Departure' that was incredible. It's set in a fantasy world facing the end of everything, and it's about a young king and queen trying to hold off that destruction. For the sake of the child they love, the two of them race across a crumbling world."

"Right, right. The world's hopeless, but the characters are upbeat and the pacing's good. It's this setup where the world is being chipped away bit by bit, but the two of them stay positive, and they clear trial after trial without a hitch, so it's the kind of adventure story that starts making you feel like things might just work out."

"But it doesn't go that smoothly, does it. In exchange for saving a vassal's life, they fail the final trial, and from there the ruin only picks up speed."

"The king and queen don't give up. They stay bright and forward-looking the whole way through. That's their one small act of defiance against the ruin. But the people won't forgive them for failing the trial. The terror of annihilation, and the madness born from it, seizes the populace, and their hands close in on the two of them. Even the vassal they'd gone to such lengths to save loses his life in the middle of it."

"In the end, leaving behind just a sliver of hope, the king and queen send their child away, out of the world. But the people who'd risen in revolt capture the two of them and put them through merciless torture."

Tsukino flipped through the pages of the club magazine.

"This scene is intense, isn't it. The violence done to those two is depicted so brutally, in such detail, you want to ask if they really had to go that far. It actually traumatized me."

"I read it back in middle school, and I couldn't sleep right for three days either."

"But," Tsukino-san went on. The same word was crossing my own mind.

"A bad end like that had me floored, and, well, I ended up joining Himurogi's lit club."

"…I'm in Himurogi's lit club too."

Tsukino-san looked surprised, but it was the reaction of someone who'd sort of seen it coming. Same for me.

"Do you write novels in the club, Asahi-kun?"

"I'm one of the more prolific ones in the club, yeah."

"Do you throw down hard at the critique sessions?"

"Oh, we do, we do."

"…But Asahi-kun, you've never once seen me, not in the club, not at school, right?"

"Never once, Tsukino-san. Even though I'm at the clubroom almost every day."

With the club magazine in front of us, we both fell silent. One guess had already surfaced, and it was an impossible answer.

"Asahi! Tsukino-chan!"

The door was flung open out of nowhere, and the two of us jumped.

When I turned around, Mom was sulking again.

"The two of you, squeezed into this cramped little room. Isn't Tsukino-chan's room bigger?"

Mom pointed toward the room next door.

"Dinner's getting cold, so eat up soon. There's cleaning up to do, too. And baths."

Having said her piece, Mom went back down to the first floor.

Tsukino-san and I looked at each other.

"I have a room?"

We stepped out into the hall and opened up the room next door, the one that was supposed to be a storeroom.

When I flicked on the light, it was no longer the room I knew.

The cardboard boxes and odds and ends that had been stacked any which way, the cleaning supplies we never used, all of it had vanished, and the freshly rewaxed flooring gleamed under the ceiling light.

A desk, a bed, a small dresser and shelf. Exactly the right amount of furniture for the room of someone we were putting up temporarily.

Realistically speaking, say my mom was pranking us with some elaborate setup. To pull that off, she'd have had to clear out the storeroom, clean it, wax the floor, and haul in new furniture, all while I was at school. No way that's possible.

Looking bewildered, Tsukino-san opened the dresser anyway.

"There's pajamas that look about my size. And the rest… yeah, it's all here."

The sight of her standing in this unfamiliar room, holding a pair of pale sky-blue pajamas, was oddly natural.

"Asahi-kun, I have a question."

"So do I. We might be thinking the same thing."

We nodded to each other.

"This is going to get personal, but… I'm going to ask you all kinds of stuff about elementary and middle school."

"That's fine. I wanted to ask you the same thing."

The names of our homeroom teachers, memories of field trips, the books and anime and movies we'd loved, the Kobayashi-kun dashing incident, the high school lit club.

"Do you use a pen name in the lit club?"

"Mikagami Owari."

"I use the same one. With the meaning of 'bad end' baked in."

We went back and forth like that, each chiming in with a "Yeah, that happened" and a "Same, same."

"My favorite villain organization in Precure is the Bad End Kingdom."

"Same here. I heard the villain org was the Bad End Kingdom, so I streamed every episode, but it had a happy ending."

"Well, when you think about it calmly, of course it did."

There were subtle differences, but almost every event had happened to me and to Tsukino-san alike. Right down to things you could only experience by being in the same class, or living in the same house.

"In that case, who was your first love, Asahi-kun?"

"A kindergarten teacher, and… did I actually need to say that?"

"Honestly, I asked on impulse. Sorry. …I hereby confess that my own first love was also a kindergarten teacher. I barely remember it, but they had this put-together, sleek look."

"You didn't have to go that far. But yeah, I remember mine being a put-together kind of teacher, too."

The topic had made things awkward. Catching each other's eyes in flickering little glances didn't help.

And come to think of it, Tsukino-san herself was pretty put-together—

"Let's get back on track." "Let's get back on track, then."

I had a feeling Tsukino-san and I were both red in the face, but at any rate we changed the subject.

"I'm Type A."

"Huh. I'm Type B."

"So there are differences after all. Well, normally that'd be a given."

"Differences… Hey, Asahi-kun."

Tsukino-san brought it up hesitantly.

"I saw your dad earlier, too, and… both of them look a lot like my mom and dad."

"Figured as much."

I'd sort of predicted it.

"But their sexes are reversed."

That, I hadn't predicted.

"Huh? The reverse of my soft, age-indeterminate mom and my mean-eyed dad?"

"Right, right, that. My mom's the one with the mean eyes, and my dad's the age-indeterminate one."

I tried to accept this impossible situation on its own impossible terms.

"I get the feeling that movie from earlier is dragging my thinking hard in one direction, though."

"Same for me."

"We might be one and the same existence, across parallel worlds." "We might be one and the same existence, across parallel worlds."

Our words overlapped.

Parallel worlds are said to exist without limit. Among them are worlds built on entirely different laws, and worlds that have traced almost the same course as my own. In short, it's possible for a world identical to this one, with the same people in it, to exist. And there are also worlds nearly identical to this one, but different in small ways.

For instance, a world where the same Masumi Asahi exists, but as a different sex.

I'd read that kind of thing in a book once, and "Infinity Heaven" said as much, too.

Part of me still thought nothing so ridiculous could be real, but right now, denying it was the harder thing.

But—

"Asahi! Tsukino-chan! Come have dinner already!"

Mom's voice had real force behind it this time, and the two of us flinched.

"That's the stage right before she gets genuinely mad." "That's right before she gets genuinely mad, yeah."

We were at an important point, but we agreed we'd better get dinner over with regardless. Our read on Mom's behavior patterns was largely the same, too.

 

*

 

We got through dinner and baths. It wasn't really the time for any of that, but dinner was as good as ever, and thinking it over in the bath actually seemed to help me sort out the situation.

After our baths, Tsukino-san and I ended up in my room again.

I sat on the bed; Tsukino-san sat in my chair.

Tsukino-san was wearing those pajamas from before. Her long black hair stood out against the sky-blue. Even though she'd dried it thoroughly after her bath, it still had a damp gloss to it. Maybe because she'd taken off her makeup, the look around her eyes was a touch softer than before.

When I noticed her bare feet peeking out from the hem of her pajamas, I found myself looking away for no clear reason. Not that I had anything to feel guilty about.

Even though this was my room, there was a shampoo scent that had never been in it before. I felt like I shouldn't let myself be conscious of it. Nothing to feel guilty about there either, though.

"Sorry. I took a while in the bath."

"No, it's fine."

I came back to myself, but I couldn't manage a smooth reply.

"So, um. I tried to gather my thoughts."

Tsukino-san had finally spoken after a long silence, but without her usual crispness. I sort of understood how she felt.

"I really do think parallel worlds are impossible. We're way too influenced by that movie. But."

"Even so, that's the one that feels most real, after all."

As Tsukino-san nodded, her black hair slid against the front of her pajamas.

"Right. In the spot where my house is supposed to be, there's Asahi-kun's house, in almost the same shape. And when we compare notes, your life and mine have followed similar tracks, and our family situations are partly different but really close. Same school, same club, and yet we've never once met at school."

Tsukino-san put a hand to her lips and thought. "This is going to sound absurd," she prefaced, and went on.

"The idea that fits best is that this is Asahi-kun's world, and I wandered in from a parallel one."

"Just to check. Can you think of any other hypotheses?"

"The theory that your parents are faking it and I'm in on it. I was lying in wait for the exact moment Asahi-kun would go see a bad-end movie. And you fell for it."

"It's got a ring of realism, but it's too pointless, and the difficulty and cost of pulling it off would be way too high."

"How about: for some reason, all of this is nothing more than an illusion Asahi-kun is seeing?"

"That explains too much, and if that were the case, there'd be no point in thinking at all."

"In a manga or novel, that'd be an 'it was all a dream' ending, the kind you're allowed to get mad about."

The two of us crossed our arms and thought it over, but the parallel-world theory still seemed like the least bad hypothesis, no matter how I looked at it.

"Actually," Tsukino-san said, picking up the silver smartphone she'd set on the desk. I used the deep-blue version of the same model. An Android, and a slightly obscure one at that, and yet we'd matched.

"While you were in the bath, I tried calling my family and sending LINE messages."

"I see. If you can get through to them, we can get an objective read on what's going on. No, wait…"

If the calls had connected, she'd have brought it up already.

"Yeah. You've probably realized it too, but neither went through. The numbers and accounts weren't there. But there's still a signal."

When she showed me the display, sure enough, there was reception. Her own plan and accounts seemed to be alive and working.

"It's not broken, is it?"

"I'd have to test it a bit more to know. Could you trade numbers with me?"

"Ah, y-yeah."

The thing I'd been screwing up my courage trying to pull off in front of the house earlier had, before I knew it, simply happened on its own.

Tsukino-san stood and came over to where I still sat on the bed. When she bent down and held the screen with her number right in front of me, her cascading black hair brushed my knee. The fresh-from-the-bath scent drifted out and spread softly.

"Oh," Tsukino-san let slip faintly.

"Something wrong?"

"Uh, um, well."

Her eyes wandered. Her cheeks, flushed and warm from the bath, seemed to have gone just a touch redder than before.

"Outside the lit club, this is the first time I've traded contact info with a boy, so it's embarrassing in all sorts of ways. …Don't ask."

"S-sorry. No, this kind of thing is a first for me too, so…"

I got that it was a bit different from swapping numbers for club business. Or rather, now that she'd said it, I was the one getting self-conscious.

So it was her first time, too, huh. Even as pretty as she is.

"Honestly. Just call me already."

A sulky expression had no business suiting her grown-up features, and yet it was cute in its own way. Thinking that despite myself, I made the call as told.

"Hello," came the answering voice, right at my ear. Tsukino-san's voice through the phone and Tsukino-san's voice from her own throat mingled together.

"It connected just fine."

When she hung up and went back over to the chair, I finally realized I'd been all but holding my breath. Because breathing in that nice scent felt somehow sinful.

While I was struggling to get my composure back, Tsukino-san went on examining her phone a bit more. I checked my own phone too, but it felt like we were both papering over that exchange from a moment ago.

At any rate, it seemed that aside from not being able to reach her saved contacts, Tsukino-san's phone worked pretty much as normal.

"The mobile games work, too. It doesn't sit right with me that almost all the apps run normally, but it's the same kind of weirdness as a room for me just casually existing in Asahi-kun's house."

"Same with you ending up cast as the best friend's daughter. Can you think of any logic behind it?"

"…Personally, I've arrived at an answer with zero persuasive power. What do you think, Asahi-kun?"

"This is leaning way too hard on 'Infinity Heaven,' but there's that thing from the movie, where when an irregular existence shows up, the world itself sometimes adjusts to accommodate it. For now, that's the line I'm thinking along."

"We really do land on the same idea, huh. Though I get the feeling it's because we watched the same movie."

In the movie, there'd been scenes where the protagonist crossed into another world and got treated as if he'd been there from the start. He'd be somebody's brother, for instance, or already registered as an adventurer in a fantasy setting.

"Neither the parallel-world theory nor the world-adjustment theory can be confirmed without looking into things more."

"True. The one thing that's certain is that this place is different from where I was."

Tsukino-san glanced toward the closet. My blazer was hanging there.

"Tomorrow, can I go to school with you?"

"So you want to find out how you're treated at school."

"Right, right. That's me for you (provisional). If it's just the family's reactions, then in theory 'everyone's lying together' could still hold up, so I want to see how other people and society at large react, too."

"Yeah. We need to look for clues."

I had no way of knowing whether Tsukino-san had really come from a parallel world. If we're talking realism, there's no way such a thing could happen. But she was just too much me.

"And… if this really is a parallel world, then let's find a way for you to get back."

Her almond eyes went round for an instant. Then they narrowed slowly.

"Thank you. Asahi-kun."

"It's nothing…"

I didn't know how to respond.

The moment I fell silent, I became conscious of Tsukino-san in her pajamas and the scent drifting off her.

Still seated, Tsukino-san looked a little uncomfortable, clasping her hands and swinging her legs. A fair amount of time had passed since her bath, and yet the redness in her cheeks wouldn't fade.

"Um… Now that I think about it, being in pajamas is kind of embarrassing, huh."

Tsukino-san wrapped her arms around herself, hugging her own body. That gesture, like she was trying to hide herself, and the faintly teary look in her eyes only emphasized how cute she was.

Suddenly Tsukino-san let out a small snort of laughter.

"Asahi-kun, you're doing the same thing."

Following her gaze, I found that I'd unconsciously ended up hugging myself too. Less crossed arms than a bashful-maiden vibe. Not cute, in my case.

"Maybe since we're one and the same existence across parallel worlds, our thoughts run alike, too."

Even I, the one who'd said it, couldn't tell whether I was deflecting or being sincere, but I felt something like blood creeping up my spine.

For no particular reason, we were both looking away.

 

*

 

Supposing we actually went to school tomorrow, how would we handle it?

After that, veering off topic here and there, we looked over Tsukino-san's room and talked through the finer details, and the upshot was that we settled on just going normally for now.

Partly because we'd gotten home late, by the time all that was done it was already past one in the morning. I really needed to sleep, so I went back to my room and burrowed into bed.

After school I'd watched a movie, and on top of that, one outrageous thing after another had kept happening. I was seriously worn out.

"Nope. Not sleepy in the slightest."

Exhaustion or not, I was still wide awake.

Up until a little while ago I'd been in Tsukino-san's room. The pajamas made me nervous, and besides, Tsukino-san's looks were, well, just my type after all. Even if it was true that we were one and the same existence, there was no way not to be conscious of a girl in the same house.

Come to think of it… I rolled over. There was a wall in front of me. On the other side of this single wall was Tsukino-san's bed.

Was Tsukino-san already asleep? Or was she, like me, restless… no, wide awake?

"The same… no, we're not."

Parallel world or not, assuming I believed her story, one thing was certain: Tsukino-san had wandered into this world.

She hadn't said anything, but she had to be anxious.

In her place, I wouldn't be able to sleep.

—Knock, knock, knock, came a sudden sound. It was from the other side of the wall.

As I wondered at it, the wall sounded again at the same pace: knock, knock, knock.

Tsukino-san was knocking on the wall.

"Ah, I get it."

I clenched my fist. I knocked on the wall the same way.

Knock, knock, knock.

"Fufu."

Through the wall came the sound of Tsukino-san bursting into laughter.

The rhythm of those three knocks on the wall was the same as when the protagonist and heroine bumped fists in "Infinity Heaven." The fist-bump Tsukino-san and I had traded at the theater.

"Asahi-kun, can't sleep?"

"Yeah. Too many surprises."

I kept quiet about the fact that I was all too conscious of the other side of the wall.

"I can't sleep either. It's just one impossible thing after another, no matter how you slice it. I don't know what I'm supposed to do."

Of course she didn't.

"But, you know. Asahi-kun, you said we'd look for a way home, didn't you."

"That's, yeah. Of course."

Even with the wall muffling sound, I could hear the rustle of her clothes. It had always been a storeroom, so I'd never once thought about how thin the wall was.

"So I feel a little reassured, and… I'm starting to get a bit sleepy."

A faint yawn threaded through her voice after that half-joking line.

"By the way, something just occurred to me."

She got that far and then trailed off a bit. I waited for the rest.

It didn't come for a while.

"Tsukino-san?"

"Oh… I thought maybe you'd fallen asleep."

Her tone struck me as somehow flustered, like she was covering something up.

"I've got a proposal. It's nothing all that grand, but, um… you know. If we're one and the same existence, then 'Asahi-kun' and 'Tsukino-san' feel kind of standoffish, don't they?"

"You think? Well, maybe so."

Actually, calling each other by given name instead of surname on the very day we met is, by my standards, closing the distance at a ridiculous rate.

"Can I just… start calling you 'Asahi'? You can call me 'Tsukino' in return."

Just being called 'Asahi' sent my heart leaping.

"Yeah. That's fine."

I answered as calmly as I could, but I think my voice cracked a little.

A short pause. Through the wall came a silence that felt like it was waiting for words.

If she really was my one and the same existence from a parallel world, what would she be thinking right now? No, I didn't know. What had just occurred to me might be nothing but my own wishful thinking. Bad-end theories, on the other hand, I could churn out endlessly.

"Tsukino."

I forced it out.

"Mm. Asahi."

The reply came back at once.

Then a giggle spilled out.

"It's embarrassing, huh."

"W-well, I'm not used to it."

Would I get used to it going forward? Was that even possible? I had no idea.

Maybe it was strange to begin with, getting nervous over calling my own self by name with no honorific. She was supposed to be me. And yet at the same time her sex was different, and her appearance matched my type to a dangerous degree.

Should I see her as myself, or as a girl? I was thinking strange thoughts. I shook my head to chase them off, but once they'd started, they wouldn't leave.

A few minutes passed after that, or maybe much longer.

In the darkened room, all I could hear was the sound of restless shifting. It mingled with the sounds from next door until I couldn't even tell which of us was making them.

"Good night. Asahi."

"Good night. Tsukino."

We'd finally gotten the words out.

My face and body were hot. Even after I kicked off the comforter, I was still hot. It was only the end of May, and yet it was strangely hot.

When I quietly got up and opened the window, the same sound came from the room on the other side.

Hair even blacker than the night sky danced in the wind.

She'd leaned her face out the window, and we traded wry smiles.

There wasn't a trace of sleepiness left in me.