I couldn't help feeling a bit anxious, though I wasn't sure why.

It wasn't simply because I was left alone at home.

In neither my previous life nor this one had I ever been abused. If anything, Kagami had raised me with excessive doting, treating me so preciously that it sometimes seemed too much.

Whether that was entirely right or not, I couldn't say. Perhaps things would have been different if I'd gotten into serious fights with other children or caused trouble everywhere. Well, at least she wasn't a "strict mother" in front of me.

Now Kagami is well into adulthood, but when I was little, she was still far too young to be considered an adult herself.

In just a few years, I'll be around the same age Kagami was then, which gives me some idea of how young she was when she had me.

...Usually, parents who aren't yet adults themselves often struggle to raise children properly. That's unavoidable.

Kagami and I were just a very unusual case.

I wondered if that child named Shii was the same way.

There are many reasons houses catch fire. Sometimes children left alone play with fire, or sometimes they try to do something on their own without parents around and accidents happen.

A colleague who works as a paramedic once told me about performing CPR on a child whose abdomen was swollen like a balloon from some severe impact. He also mentioned transporting a child who hadn't eaten anything for days.

Was Shii like that too?

Maybe I was feeling anxious because I was overlapping those children's situations with hers. Somehow, I didn't think her father was someone capable of normal thinking.

I looked at the clock.

About ten minutes had passed.

There was still no sign of Kagami and Dad returning. It would take about five minutes to get to that house, so it wasn't strange, but still.

I could have done something else to pass the time, but I couldn't bring myself to.

I still didn't understand why I felt so anxious. Was it because this child might have had a past similar to what mine could have been? Perhaps because I could have been in her position? If I hadn't been lucky enough to have someone like Kagami as my mother, I surely would have—

Shii.

Suddenly, that name flashed in my mind.

Why was that? When I first heard the name earlier, the situation was so intense that I might not have noticed this feeling passing through me, but looking back, I felt a strange sense of discomfort with that name.

This feeling was similar to when I first heard Souta introduce himself.

"..."

A memory of knowing something from long ago.

But the puzzle piece couldn't even take proper shape in my mind, so I couldn't fit it into my memories. Had I met the two of them when I was young? I did live in Tokyo when I was little. I barely remembered the names of my kindergarten friends unless we were really close.

So why had I reacted specifically to the name Shii? I wasn't sure.

My anxiety only grew. Looking at the clock, only seven minutes had just passed.

"...Yeah."

I nodded to myself.

It's fine.

They must be nearby anyway. I hadn't even heard a car leaving.

I thought it would be okay to go out briefly and walk around the neighborhood a bit. Just to check from a distance if Kagami and Dad were doing all right.

I hadn't changed my clothes anyway. There was a little blood on my pants, but they were dark-colored so it wasn't very noticeable.

I opened the door and went outside.

Just in case, I always carry my key with me. I took it out of my pocket, locked the door, and headed out to the street, looking around nervously for no particular reason.

And with inexplicably cautious steps, I headed in the direction Shii had gone.

*

Bad luck.

Yes. Souta was staying after school to play with his friends.

I was a girl—well, that wasn't really important, but I had no intention of joining in their ball games anyway, so I just went home.

Usually, we didn't show that we were particularly close at school. We both knew it would develop into something very troublesome.

We were gradually moving past the age where boys teased and bullied girls, or girls openly showed their dislike for boys, but we weren't completely past that strange awkwardness yet.

I didn't feel that awkwardness myself, but I knew the kids around me did. I wasn't sure what emotions Souta felt, though.

"Kotone."

When I heard someone calling me from behind, I couldn't help but flinch in surprise.

"Souta."

When I turned around, Souta was holding a soccer ball in his hand. Did he bring it with him to school? There should be balls at school too.

Well, he's a boy. If he bought an expensive soccer ball, he might want to show it off to his friends.

No, more importantly.

"What are you doing here?"

"Ah..."

I belatedly realized that the path Shii had taken wasn't very different from the one Souta usually took.

I was so anxious that I hadn't thought about running into a friend on the street.

But I couldn't tell Souta about Shii either. That was—

"..."

Wait.

Hold on.

Did I ever hear Shii's family name?

"Kotone?"

When I had a blank expression on my face, Souta approached me and asked.

Come to think of it, what did Shii say?

She said she was going to meet her brother.

And Souta had told me before that he had a younger sister. There seemed to be some story behind it, so I hadn't asked too deeply.

Was I jumping to conclusions?

Was I just forcibly connecting Souta and Shii in my mind? Was this the kind of thing that would upset him if he heard it?

"Kotone."

"Ah, yes."

Only after Souta called me once more was I finally able to respond.

"What's wrong? Did something happen? Is that why you're outside?"

"Um... no, that's not it."

What should I say?

My instinct was telling me to quickly take Souta in a different direction.

I didn't know if Souta was really Shii's brother, but just the possibility that he might be made me realize that Souta would be greatly shocked if he saw Shii.

But—how?

Our house was empty. But taking Souta to our house would be...

No, that's not it.

Rather, because of that, maybe that's exactly what I should do?

"Souta, perhaps—"

"Yeah?"

Had I opened my mouth with too serious an expression?

Souta responded with a slightly bewildered look. But it still seemed okay for now. My expression wasn't that serious—

However, before I could continue, a voice rang out through the quiet residential area. Unfortunately, it was the middle of the day without a single car passing by, so the voice carried extremely well.

All the way to where we were standing.

"What are you doing here?!"

It was a voice I'd never heard before.

It was different from when Dad raised his voice. If Dad's voice was thoroughly trained to deliberately scrape at the other person's emotions, this voice, in contrast, was one that truly couldn't contain its emotions.

But I was much more frightened by the voice that followed than by that one.

"...Dad?"

Souta murmured, looking in the direction of the sound.

At those words, I felt a chill run down my spine.

I could finally understand the source of the discomfort in my mind. Who that girl named Shii was.

Shii was Souta's sister.

And—

Souta started running. Without even paying attention to me standing right next to him. Thump, thump, the soccer ball he was holding bounced on the ground, and I instinctively bent down to pick it up.

"Souta!"

I shouted a bit belatedly and followed after him.

When I called his name, that strange sense of discomfort revived.

The same kind of discomfort I felt when I first called Souta's name.

That discomfort I had forgotten during all the time I'd been meeting and talking with Souta. The discomfort I felt when I first heard the name Shii.

But I still couldn't be certain of the nature of that discomfort.

Was it related to memories of this world I had entered? Had I actually remembered something from my previous life?

I wasn't sure.

More importantly, there was something I needed to do now.

I didn't know what exactly I should do, but—

"Souta!"

I ran hard while shouting Souta's name loudly. Somehow, I was still holding onto the soccer ball.

Souta was running ahead, and further ahead, I could see something.

A house that seemed a bit larger than ours, somewhere between a mansion and a regular house.

And standing in front of that house was a man slightly smaller than my dad.

That man, his face flushed red with anger, shouted:

"Didn't you agree to live with your mother! That woman you resemble!"

"..."

"Father!"

Souta shouted.

The man's gaze turned toward Souta.

Ah.

So it was true.

Shii really was...

Kagami, who had turned to look in our direction a bit late, had a surprised expression when our eyes met.

Kagami had her hands on both of Shii's shoulders.

Shii, despite hearing such things from her father, was looking toward Souta.

"Brother...!"

Shii cried out.

And shaking off Kagami's hands, she ran toward Souta, stumbling as if about to fall.

Souta caught her and held her tight.

And embraced her firmly.

"..."

The adults around us. And me, panting for breath.

We all froze, unable to say anything at the sight before us.