Somehow I Ended up Dating the Perfect Female Classmate, but My Sister Found Out and They're Turning Into Yanderes - Chapter 18-19

Chapter 18: Temporary Enrollment (2)

“It’s impossible not to fall for Rinka after seeing her change like that.”

I’m in a Japanese class at the tutoring center.

I’m still in temporary enrollment, but at this point, it’s pretty much certain I’ll join for real.

The classroom is a smaller version of a school classroom, with just over ten students.

I’m at the back by the window, so I stare outside and think about today.

Things got wild when I got home.

Rinka walked me home like she was escorting me.

Ayuka, who was waiting at the entrance to go to the tutoring center with me, saw it and tried to pull us apart like she was going to punch someone.

Of course, she was no match for Rinka and got brushed off easily.

Then Rinka asked me what I wanted for dinner.

Rinka’s never asked me about the menu before.

Thinking Ayuka might pull out a cutter or something, I said hamburgers and left.

“Thanks to that, Ayuka’s been in a bad mood.”

On the way to the tutoring center, Ayuka seemed totally out of it.

Not like she was zoned out, but more like she was glaring ahead, probably imagining me or Rinka as a punching bag.

“Is she even paying attention in class…?”

With that attitude, she’s probably not absorbing anything.

Well, I’m not one to talk, since I’m thinking about today instead of focusing on the lesson.

Do I really need to study Japanese at a tutoring center?

Reading comprehension comes from reading books regularly.

Luckily, I’ve got my erotic novels, so I’m good at modern Japanese.

“Okay, that’s it for today. Everyone, study on your own.”

The teacher left with that usual line.

Most of the students in the class hurried to pack up.

It’s past eight o’clock.

They probably came without eating dinner.

I’m one of them, but since I have to wait for Ayuka, there’s no rush.

“Oh, but Ayuka only had one class today, right?”

I don’t know if high school and college prep classes have the same schedule, but she might already be waiting.

I left the classroom and passed the counter.

“See you later~”

I ignored the tutor’s greeting and went to the entrance, where, as expected, Ayuka was waiting, looking grumpy.

“Done with class already?”

“…Today was a class placement test. You can leave once you’re done.”

The high school prep classes here have a ranking system, with cooler class names for higher-scoring students.

A test once a month decides if you move up or down.

“So… what class are you in, Ayuka?”

“The Ultimate Class, obviously.”

The name alone tells you it’s the top class.

…Why are all the Nuregami sisters so smart?

But Ultimate Class…

Tutor, can’t you come up with better names?

“More importantly…”

Ayuka turned her hateful glare on me.

“What was that earlier?”

“What?”

“Don’t play dumb. Why were you and Rinka-neesan so close when you came home?”

I knew this was coming.

“I’ve never seen Rinka-neesan like that. It was like she was wrapping you up…”

Ayuka’s voice trembled with anger.

…Is it really worth getting that mad over?

Even if Rinka suddenly got all sweet on me, I don’t think it should ruin Ayuka’s mood.

“Hey, what really happened today?”

“What happened? Well…”

A lot happened, honestly.

Rinka’s change is 100% because of Kirino-san.

When Rinka found out I’m dating Kirino-san, she completely changed.

But why did she change so much just because I’m with Kirino-san?

The most likely theory—no, the only one that fits—is that, like a yandere ASMR script or a harem gal game, she got jealous of Kirino-san and snapped.

So, like Rinka said, all this time, it really was the whip of love…

My real sister’s been like that all along.

Knowing this, how could I not get excited…?

“Hey, why are you quiet all of a sudden?”

…I don’t think Ayuka has any special feelings for me.

It should be fine to tell her the truth.

“Well, actually—”

“Hey, Kiyoto-kun!”

—

Chapter 19: Third Sister and Girlfriend

“Hey, Kiyoto-kun!”

Huh? What’s that beautiful voice?

It feels so familiar.

“K-Kirino-san!?”

Yes, it was Kirino-san, so perfect that she once made the school’s bachelors think she’d been transported into a doujinshi world.

“Huh? Who are you? We’re kind of busy here.”

Hey, Ayuka!?

Why are you so hostile?

“Uh, um, who are you…?”

Kirino-san flinched at Ayuka’s aggressive tone.

“I’m this guy’s sister. Who are you?”

Calling your brother “this guy”?

But that coldness is part of Ayuka’s charm as a girl!

“Sorry. I should’ve introduced myself first.

Nice to meet you. I’m Kirino Kinui, Kiyoto-kun’s classmate and girlfriend.”

“…Huh?”

Unlike Rinka’s reaction, Ayuka let out a “huh?” that showed she genuinely didn’t get it.

“What? Some kind of penalty game? Someone forced you to say you’re his girlfriend?”

Yeah, most people would think that.

With Kirino-san’s model-like figure and that voice.

“It’s not a penalty game or anything. I’m genuinely dating Kiyoto-kun.

Also, I don’t think you should talk about your brother like that.”

Kirino-san’s lecture was seriously powerful.

“Huh? You’re really dating? You and my brother?”

“Yup. I confessed to cute Kiyoto-kun, and we started dating.”

C-Cute…//

When my girlfriend says that, it’s good for my “little buddy’s” health.

“No way… That’s a lie…?”

“Little sister? What’s wrong? Oh, by the way, how many sisters do you have, Kiyoto-kun?”

“I have four sisters, and I live with the second, third, and youngest.”

“Four sisters, huh. What’s this one’s name?”

“Ayuka. The one you met at school was Rinka.”

“Ayuka-chan, huh? Nice to meet you, Ayuka-chan.”

Kirino-san said with a smile, reaching to pat Ayuka’s head.

Ayuka swatted her hand away.

“…Don’t touch me.”

Unlike Rinka’s chilling low tone, Ayuka’s voice was like a lump of pure hatred.

“H-Hey, Ayuka.”

I stepped closer to scold her.

“It’s fine, Kiyoto-kun. Ayuka-chan’s probably just shy. She’s not used to me being your girlfriend yet.”

Ayuka, shy?

Her aggressive tone earlier felt far from shy…

“…Let’s go home.”

As Kirino-san and I talked, Ayuka grabbed my shoulder from behind.

“Ow, that hurts, hurts, hurts!”

No, seriously, it hurts.

Does Ayuka have this much strength?

She doesn’t look like a muscular girl, just a tough-looking, pretty middle schooler.

Where’s all this strength coming from?

“Ayuka-chan, Kiyoto-kun doesn’t like that. Talk to him!”

“Shut up!!! Come on, let’s go!”

Desperate to get me away from Kirino-san, she skipped the elevator and dragged me down the stairs.

It hurts, it really hurts!

You know how online buddies always say it.

Pain is the way out.

“Let go already!!”

When we reached the first floor, I finally shook Ayuka’s grip off my shoulder.

My shoulder’s definitely red now.

“…What’s with her?”

She’s calling Kirino-san “her” now…

“She was going on about being your girlfriend. What’s that about?”

“What’s it about? She’s just my girlfriend.”

“…I never thought I’d hear the word ‘girlfriend’ from you.”

Muttering sadly, she quickly hopped on her bike.

“…I’m going home first today.”

“Huh? But we’re supposed to go together…”

“…Let me go alone today.”

With that, she pedaled off faster than usual.

When Ayuka was out of sight, I locked my bike.

“…This is gonna be awkward when I get home.”