I slowly opened my eyes when I heard my grandmother waking me up. It was eight in the morning; my parents had already returned from the hospital.
"Raiden, you should go greet your new little sister. Your parents are in the living room."
"Of course, Grandma!" I replied, playing the role of an excited child eager to meet his new sister—though part of me truly was curious.
After washing my face, I headed to the living room, where my parents were holding a small baby. I walked up to them and looked at my new sister with curiosity.
"Raiden, I'd like to introduce you to the newest member of the family. As her big brother, I hope you'll protect and love her dearly," my father said.
In my mother's arms was a baby girl with hair as black as mine, but with dark eyes. At least she wouldn't draw as much unwanted attention at school as I did. Still, if boys started showing interest in her, I might have to play the overprotective brother.
"What's my sister's name?" I asked eagerly, curious about the name my parents had chosen.
Maybe it wouldn't be as odd as mine… I once looked up the kanji for my name, and let's just say the result wasn't very encouraging.
With a joyful smile, my mother said, "Raiden, please give a warm welcome to Tsurumi Rumi, your little sister!"
"That's a beautiful name," I said, genuinely impressed.
For some reason, the name sounded familiar, though maybe I had just heard it somewhere or read it online.
Was Rumi a common name? I supposed it could be, though it reminded me of our family name.
Tsurumi Rumi…
It felt strangely familiar, but it wasn't unusual. Our last name was Tsurumi, and her first name was Rumi—they had just chopped off a few letters. My parents sure were lazy.
"Look, dear, our son is so happy he looks like he's on cloud nine," my mother said fondly.
"You'd better be a great big brother, Raiden," my father added, patting my head.
"Of course!"
After a few more minutes of playing the curious older brother, I went back to my room. Normally, I wouldn't have dwelled on something like this, but my sister's name kept echoing in my mind.
Still, it wasn't as if this was the location of the Philosopher's Stone, so I tried not to think about it anymore.
…
Days passed after my little sister's birth. School was the same as always—nothing exciting—but ever since that day, something kept nagging at the back of my mind.
I felt like I had heard my sister's name somewhere before, and it was from long before this life. But that would have been strange, since the only Japanese words I remembered hearing back then came from anime or light novels I had read.
Back then, I preferred medieval or reincarnation stories with magic and fantastical worlds, but I also read a few romance novels or ones set in everyday life. I was a teenager at the time, so I was interested in all sorts of works—I couldn't say exactly where I had read it.
Of course, it wasn't as if I had somehow reincarnated into a world where those stories or characters actually existed… right?
Most likely it was just a coincidence—after all, authors had to get their character names from somewhere.
I was probably overthinking something from the past. Maybe I was still just too stubborn…
…
Saturdays had always been some of my favorite days, whether in my previous life or this one. Sure, I couldn't go out drinking to complain about work now, but I also didn't have to work, so I guess it balanced out.
My routine was simple. As a kid, all I could really do was get up, wash my face, eat breakfast, finish any homework, then play or waste time on my tablet while browsing the news online.
Staying informed was always useful—something I had learned back when I had to negotiate with potential clients and secure deals for the company. Who in their right mind sent the rookie to handle high-value contracts?
Let's just say it was a habit that stuck with me.
Not that the news was particularly exciting—just the usual headlines:
-Keiyo Line reported delays during rush hour due to technical inspections.
-Expansion work began at Kaihin-Makuhari Station.
-Sobu High students to take part in earthquake drill this week.
-Stray cat became a local celebrity after being adopted as a bookstore mascot.
-Yukinoshita Group led real estate expansion in Chiba Prefecture.
Daily news. Although I had to admit, as a former employee of a company, the Yukinoshita Group had managed to stay on top despite others trying to knock them off their throne. For a company that had been around for so many years, driving them out of the market was impossible.
Even an idiot would have realized it was foolish to go up against something so much bigger and more powerful—simple common sense.
With nothing else interesting to see, I set my tablet aside and lay down on my bed, staring at the ceiling.
It might have sounded strange, or maybe I was just an idiot, but I felt like I was ignoring something.
Something in my mind told me I had already been given several clues, but if I couldn't remember them, I couldn't connect the dots.
Recapping what I knew: I was born in Japan, specifically in the city of Chiba, my last name was Tsurumi, I had a little sister named Rumi… after that, the rest was just what you'd expect from the daily life of a six-year-old boy.
Although… some things I had read lately felt familiar.
Sobu High, Yukinoshita…
Just like my sister's name, I felt like I had read about this before…
Maybe I should have kept a diary of all my memories from my past life?
"No point. I give up."
Several minutes passed before I finally threw in the towel. I had thought about it in many logical ways, but nothing seemed to work.
Or maybe my way of analyzing things was wrong?
In my previous life, the only chances I'd had to learn anything about Japan were through anime or light novels, so I dismissed that idea right away. But… what if I went down that path?
A hypothetical case—which might sound stupid even to think about—but still, I gave it a try. No one truly knows what comes after death. The most common beliefs are eternal rest, or heaven and hell. Some cultures talk about reincarnation, and having experienced it myself, my situation already felt far too unreal.
In certain Japanese works, reincarnation after death was treated as something normal, and I guess I fit that mold—except I didn't get any special powers or cheat abilities to make my life easier. Not that I'd need them, since there wasn't a dragon or demon king waiting to wipe out humanity.
Back to the point. I had been reborn in Japan, surrounded by familiar names. If I thought about it like a teenager with too much free time, the option would be that I reincarnated into one of the stories I once read.
It didn't make much sense, but I kept following that line of thought. If these names sounded familiar, and if I excluded every fantasy world, that only left stories set in normal society—a very small number to begin with.
With that, I had already made a big step forward. All I needed was to narrow it down to a few key details: Chiba, Sobu High, Yukinoshita, Tsurumi Rumi.
Chiba: capital of Chiba Prefecture.
Sobu High: a prestigious school, famous for helping students get into university.
Yukinoshita: surname of one of the most powerful families in the area.
Tsurumi Rumi: my little sister, black hair and black eyes—common traits, really.
Nothing definitive came to mind… but if I insisted on overthinking it, then both Yukinoshita and Tsurumi had to be tied to characters from a work. My family wasn't flashy, so let's say I was a side character, while Yukinoshita belonged to the main cast.
Adults rarely played the leads, so it had to be about their children.
A quick internet search gave me a news article about the Yukinoshita family, highlighting their two daughters. On one side, a girl with black hair and violet eyes, maybe a few years older than me. On the other, a girl my age with black hair and striking blue eyes.
Coincidence—or not—but the younger one's name was Yukino. Yukinoshita Yukino. Just like my little sister, her given name clearly derived from her family name.
Was that really coincidence? Or something written into a pre-established script?
If Yukinoshita Yukino was a main character, she'd clearly become important later. No story I remembered had focused on elementary school kids, which meant her relevance would begin in high school. And that's where Sobu High came in—the stage for the supposed story.
I felt like the answer was right on the tip of my tongue, as if I just needed one more push to remember. Authors rarely picked names at random. They often chose ones that reflected a personality or carried some deeper meaning.
From my kanji lessons—and honestly, more from online searches than my own knowledge—I knew that Yukino could be interpreted as "snow."
And snow, reflected in someone's personality, suggested a person cold, reserved, and refined. Exactly what you'd expect from the daughter of a distinguished family. Which meant dealing with her would be an absolute headache. Maybe, with some luck, she could make a few friends, most likely someone with a personality similar to her own.
That would make him reserved, cold, and solitary as well.
"Oh!"
It finally clicked.
If my memory served me—or at least the vague fragments I had—I once read a story for that exact reason: the personalities and relationship between the main characters.
I had grown bored of the usual cliché—the nerdy girl and the popular guy—so I picked up a work where both main characters were bad at socializing, and one of them was extremely cynical. That was the charm.
I never found out how it ended, since the author put it on hiatus. But back then there was this "rule" that the girl on the first cover was the winner, so there wasn't much room for doubt.
That answered why those names felt so familiar.
"I really overthought this… oh well."
Feeling like my brain had been working overtime, I lay back to relax. Maybe a nap would recharge me. Later, I'd play some games or watch anime on TV. My eyes closed, and I drifted toward sleep.
"EHHHHH!!!???"
I jolted upright.
Why the hell was I sleeping!?
I had just realized all the pieces I connected pointed to one of the stories I read in my previous life… and I simply decided to nap after that?
Maybe my brain couldn't process something so absurd actually happening. I mean, it was one thing to reincarnate after dying—but reincarnating directly into a story I once read?
Am I dreaming?
I pinched my arm. A faint sting.
Not a dream.
Then could this be a one-in-a-million coincidence? If so… was this really the only work that existed in this world?
There were fanfics where multiple series were mashed together into one setting. Thinking about it now, that didn't sound so far-fetched. Still, I wasn't Sherlock Holmes who could solve everything without evidence.
Realistically, everything pointed to my hypothesis being correct.
And now, only one question remained in my mind:
How the hell did I end up inside the world of a light novel?