Somehow I Ended up Dating the Perfect Female Classmate, but My Sister Found Out and They're Turning Into Yanderes

Chapter 58: Fuzuha’s Perspective

“What should I do… If this keeps up, our family will fall apart…”

I muttered to myself, holding my head in my hands, alone in my room.

When I think about it, I believe our siblings were really close.

Ayuka-nee might be a bit harsh, but she cares about me and big brother.

Rinka-nee takes care of us around the house in place of our mom, who’s almost never home due to work trips.

And big brother, who’s a bit clueless but makes being around him fun.

I really enjoyed spending time at home with these three, and more than anything, I was proud of our sibling bond.

…But lately, everyone’s been acting strange.

Ayuka-nee keeps snapping at Rinka-nee for no reason.

Rinka-nee ignores Ayuka-nee and treats big brother like he’s something precious.

And… big brother is getting close with that Kirino girl, someone we’ve never even met before.

Everyone’s acting weird.

But that applies to me too.

When I opened big brother’s room to play games together, I saw him playing online with some unknown girl. I couldn’t think straight and yanked the game cord out.

Not only that, when I saw big brother and that girl walking home together, I don’t remember what she said to me, but I instinctively tried to jump at her.

I’m already plenty weird myself.

And it’s scary.

I’m afraid that one day, without realizing it, I might hurt not just that girl but big brother too.

But what scares me even more…

Is that our sibling bond might completely break, and we might never get it back.

“What should I do… what should I do… what should I do…”

If this continues, that fear will almost certainly become reality.

So, what’s causing this situation to get worse?

I don’t even need to think about it.

It’s that Kirino girl who’s been clinging to big brother.

The other day, that girl even stayed over at our house.

I tried to jump at her again, but I stopped myself because I knew it would cause trouble for big brother.

Instead, I threw every insult I could think of at her to make her leave.

Then her vibe suddenly changed, and even though I was scared and teary-eyed, I kept hurling insults.

Luckily, Rinka-nee stepped in to mediate, but if it had gone on, I’m sure that girl would’ve hurt big brother, who would’ve tried to protect me.

In other words, all my actions so far have just been a bother to big brother.

When it was time for dinner, Ayuka-nee revealed she kissed big brother, and that girl strangled Ayuka-nee hard.

I tried to pull her off, but the strength difference was too much.

I just watched as big brother caused trouble and Ayuka-nee got knocked out.

I felt so frustrated and pathetic about myself that I just cried in my room that day.

I know that girl is the root of all this.

I know it, but I’m powerless to do anything.

Why am I so weak?

Why don’t I have the strength to protect what’s most important to me?

“…”

Tears started spilling again.

What am I doing, shutting myself in my room alone like this?

“…It’s already summer break, huh?”

I wonder what my friends are doing right now.

Maybe they’re struggling with summer homework or going to the beach with their families.

But I can say they’re all having a more fulfilling summer break than me.

“Oh.”

That’s right. Speaking of summer break…

An idea crossed my mind, and I went downstairs to check the phonebook by the living room phone.

“…Shinkai Girls’ Academy Dormitory.”

Listed there was the girls’ dormitory where our eldest sister, Satsuna-nee, lives.

“…”

I stared at the phone number, torn.

I can’t fix this cracked sibling bond on my own anymore.

So…

If it’s Satsuna-nee…

After wrestling with it, I dialed the number with shaky hands.

—

Chapter 59: The Queen’s Arrival Announcement

“Hey! Big brother and Rinka-nee, welcome back!”

Fuzuha greeted us with a huge smile as we entered the living room.

“Uh, h-hey, I’m home… Is Ayuka gone again today?”

“Yeah! She said she’s eating out with friends tonight.”

…Fuzuha’s smile is so big it’s kind of scary.

It’s not like the crazy smiles of Rinka or Kirino. It’s a pure, heartfelt smile, like she’s relieved about something.

“By the way, I already bought dinner for you two!”

On the table were convenience store bentos for me and Rinka.

“Thanks.”

“…”

Rinka just stared silently, switching between the bento and Fuzuha.

“Fuzuha.”

Rinka’s dead-serious voice echoed.

“Hm? What’s up, Rinka-nee?”

“I’ll ask straight. What happened?”

So Rinka noticed something off about Fuzuha too.

Lately, she’s been pulling cool yandere moves while still keeping a close eye on her little sister.

As expected of the future… No, no, stop it.

Even thinking that in my head might tip Kirino off.

“What happened? Nothing happened.”

“You don’t need to hide it. How many years have I been your big sister? If I missed even a small change in you, I wouldn’t be Nuregami Rinka standing here.”

Is she getting hooked on that cool way of talking lately?

“Really, there’s nothing for you to worry about, Rinka-nee… If I had to say, it’s that Satsuna-nee is coming back soon.”

“…What?”

For once, my voice and Rinka’s overlapped.

That’s not just rare—it might be a first.

“Uh, Fuzuha? Is that a joke…?”

“Satsuna-nee said so on the phone earlier, so it’s probably true. You know she’s not the type to joke, right?”

Satsuna… is coming back.

That queen-like eldest sister, Satsuna…

The one who trained me to be a masochist.

You might think a queen-like personality is my type, right?

But with Satsuna, the trauma is way stronger.

Sure, most of what she does gives me pleasure, but sometimes she makes me suffer without holding back.

Oh… just remembering it makes my “son” stand up and tremble at the same time.

“Did Sister herself say that?”

See, even Rinka calls her “Sister,” so you get how intense she is.

“Yeah, specifically, she’s coming back tomorrow night.”

Got it, during Obon… Wait, tomorrow!?

Don’t people usually come back during the Obon holiday?

“…And why do you look so relieved about Sister coming back? …Don’t tell me!!”

“…You figured it out, huh. I asked Satsuna-nee to come back.”

What!?

Are you serious!?

Why would you jump into magma like that?

“…Just to be sure, why did you call Sister back…?”

Rinka asked Fuzuha, her emotions raw.

“…Because everyone’s been acting weird lately.”

Fuzuha’s voice and body started trembling.

“Before, Rinka-nee used to take care of everyone properly, but then you got violent with big brother, the police came to our house, and now you’re super sweet to him and treat Ayuka-nee like a stranger.”

Is “super sweet” the right way to describe how she treats me?

“And Ayuka-nee’s been cold lately and is barely home.”

True, Ayuka used to check on Fuzuha now and then, but lately, I haven’t even seen them talk.

“And big brother’s been all over that Kirino girl and even brought her to our house the other day.”

To be fair, I didn’t know she was coming either.

“I just… I just want us to go back to being the close siblings we used to be. That’s all I want.”

Rinka stared silently at Fuzuha, who was tearing up as she spoke.

I couldn’t read any emotion on her face.

It wasn’t full of raw emotion, but it wasn’t completely cold either.

“…So you think Sister can fix that bond?”

“I… don’t know.”

Yeah, fair.