I was sure Kazune would have gone home by the following Monday, but nope, she was still Kazune.
“How many days has it been?” I asked.
“Exactly one week.”
We sat at the table at our usual karaoke lounge as she gave me her status report. By this point, our sunny optimism was fading, and we were both starting to get worried that she’d never shift back.
“So I asked my…parallel father about long-distance shifts,” she continued.
“What did he say?”
“They’re considered to be extremely uncommon, and because there are no proven clinical case studies, little is known about them.”
“I see.”
“One working theory suggests that long-distance shifts are more common in older people—that it could explain the root cause of dementia. But even then…” she trailed off.
“Yeah, you’re way too young for that.”
“I’d like to think so, at least!”
Ultimately, we had no clue what to do.
“Well, I do have one idea. You could tell him what’s going on. Maybe they could scan you at the lab or something?”
She seemingly hadn’t told anyone but me she was from a parallel world. Given that she was wearing a prototype IP band, I thought she was probably obligated to report that sort of thing, but whatever.
“I’m considering it as a last resort, but…I just know they’ll study me like a lab rat. Ideally, I’d like to go home the natural way, with no one else finding out.”
I couldn’t really argue with that. Nobody would want to be a laboratory’s guinea pig…and besides, I kind of liked being the only person special enough to know the truth.
“After I get home, I’ll try asking my dad too. Supposedly he’s pretty high up the chain of command, so maybe he’s heard the latest developments,” I said.
“Please do. I’ll take whatever sort of hint I can get.”
The mood was too gloomy to sing karaoke that night, so we went straight home instead. When I arrived, I immediately called my dad on the phone. His work schedule was erratic, so there was really no guarantee he’d answer, but this time I got lucky.
“Hello?”
“Hey Dad, it’s me, Koyomi.”
“What’s up, kiddo?”
With Dad, I didn’t need to waste time making small talk. Instead I cut to the chase. “I have a question for you. Is it possible to voluntarily shift to a world of your choice?”
In every work of fiction that featured parallel worlds, there was nearly always a way to do just that. Its difficulty varied widely—sometimes it involved specialized machinery, and other times, characters just closed their eyes in the dark and wished for it really hard—but if parallel worlds existed, then a method for voluntary travel was all but certain. Maybe, just maybe, there was a way to send Kazune home again.
In fact, I had an idea of how to achieve it.
Approximately five years prior, when I shifted to a world where my grandpa was still alive, I awoke to find myself in a strange pod-like enclosure at the Imaginary Science Research Institute. Looking back, it seemed so obvious—surely it had to be a machine designed to send people to parallel worlds. Granted, I kept that experience a secret so I couldn’t say anything outright, but if my suspicions were correct, it was possible he’d volunteer some sort of information about it.
Unfortunately, the answer he gave was a little vague for my liking.
“Theoretically…yes, it’s thought to be possible. In fact, we’re researching it at the lab. But right now, we don’t have the technology to make it work. I’d say it’ll take us another ten years before we get there.”
Ten years? No way in hell could we wait that long. But at the very least, this answer did seem to confirm my suspicions about that pod.
The very next day, I headed to school, planning to let Kazune know that voluntary shifting was at least theoretically possible. On my way there, however, I happened to spot her on the street up ahead.
Luckily, none of our classmates were around, so I ran up behind her and whispered, “Morning, Kazune.”
At that, she whipped her head around to look at me, then jumped back in fear. Her reaction told me everything I needed to know.
Kazune—no, Takigawa-san—hastily looked down at the IP band on her wrist. I couldn’t see the number myself, but I suspected it was something small, like 000 or 001. At the very least, it most likely wasn’t 085 anymore. Kazune had gone back home.
Then, without a word, Takigawa-san turned and dashed off toward campus.
During a shift, the subject switched places with their other self in the parallel world. That meant that Takigawa-san had spent the past week in World 85 with Koyomi. What had they talked about? And now that she was home again, how did she feel about me?
Sad to say, I wasn’t yet mature enough to let it all end without trying to find out.