Chapter 47: Keep your enemies close

I still hadn’t fully grasped the situation.

No, how did things even end up like this in the first place?

I was sure that when Kim Harin and Seo Yuna met, a chilling tension would fill the air.

Kim Harin’s yandere tendencies would explode, and Seo Yuna, oblivious as ever, would make the atmosphere even worse…

That was the development I expected.

But it was unbelievably peaceful.

Far from being tense, the two of them were actually chatting and laughing together.

“Yuna unnie, you’re really popular at school, aren’t you?”

“No, not really. I’m just kind of friendly, I guess?”

“Come on, you’re totally pretty.”

“Oh, really? You’re pretty too! Dohyun’s little sister is so cute!”

…What?

I didn’t see this coming.

The atmosphere was way too good.

I looked back and forth between the two, feeling dumbfounded.

‘Had I been worrying for nothing?’

“But Harin.”

Seo Yuna took a step closer, glancing at me with playful eyes.

“I heard a rumor that Dohyun is a siscon. Does he spoil you a lot at home?”

“Mm, yeah! We go grocery shopping together sometimes! And he pats my head, too.”

“…Really?”

Seo Yuna glanced at me, a smirk playing at her lips.

It was a teasing smile.

And then—

“But he doesn’t usually walk me to school. He says it’s a hassle.”

Kim Harin spoke in a very quiet voice.

‘Huh?’

I instinctively turned to look at her.

Something about the way she said that…

It felt off.

Seo Yuna immediately picked up on the nuance and responded.

“No way~! Dohyun, that’s so mean. How could you refuse when such a cute little sister asks to walk together?”

Seo Yuna playfully nudged me.

I quickly raised my hands, ready to explain myself.

“No, it’s not like that—!”

“Hmm~?”

And then.

“I know, right.”

Kim Harin slowly nodded.

Then, she smiled softly at Seo Yuna.

“My brother isn’t usually like that… But I guess he walks to school with you pretty often?”

Wait.

That sounded like a normal question, but something about it sent a chill down my spine.

Seo Yuna was still smiling, but she blinked as she looked at Kim Harin.

“Huh? Oh, well, yeah, we’ve walked together a few times!”

“I see.”

Kim Harin nodded.

Then, very subtly, the tip of her finger brushed against my sleeve.

A shiver ran down my spine.

This was—

A warning.

…She’s doing it again.

“So, are you two going to keep walking to school together?”

Seo Yuna still didn’t seem to grasp the atmosphere.

“Well, we go the same way, so—”

“I see.”

“But, oh no. What should we do? From now on, I’m going to be walking with my brother too.”

Seo Yuna blinked at me.

“Really? Then we can all walk together!”

Read the room.

For a brief moment, Kim Harin’s gaze wavered.

“Ahaha, walking together as a trio sounds nice.”

“Right?”

Seo Yuna smiled and took Kim Harin’s hand.

Meanwhile, Kim Harin… subtly glanced at me.

Her lips curled up slightly.

‘…What is this?’

I had expected Kim Harin to lose her mind with jealousy and treat Seo Yuna like an enemy.

Instead, she was acting friendly.

Somehow, I felt like I was the one being left out.

And I had a gut feeling.

A yandere is most dangerous when they’re quiet.

I had already experienced it once.

***

“Shall we go?”

Kim Harin linked her arm around mine.

Seo Yuna gave me a sideways glance before asking playfully, “Dohyun, were you always this affectionate?”

“What?”

“You’re really sweet to Harin.”

I responded with a nonchalant smile.

“Well, she’s family.”

“Lucky. I’m an only child.”

Seo Yuna turned to Kim Harin.

“I wish I had a cute little sister like you.”

“You can have her. I’d gladly give her away right now.”

“Heehee. Thank you.”

Kim Harin responded with an innocent smile.

But her eyes—

They were eerily void of warmth.

The moment I saw that expression, cold sweat trickled down my back.

That was the look of a yandere saying—

‘Don’t act too friendly with him.’

Seo Yuna, however, remained blissfully unaware.

“But usually, siblings don’t get along that well. It’s kind of surprising.”

“Huh?”

“I mean, I’ve been watching you guys, and you keep walking arm in arm.”

I hesitated for a moment, trying to come up with an answer.

“Uh, well…”

And then.

Kim Harin spoke with complete composure.

“We always walk like this.”

Seo Yuna blinked, looking back and forth between us.

“…Always?”

“Yes.”

Kim Harin was still clinging naturally to my arm.

Something felt off, but I decided not to say anything.

An odd tension filled the air.

A subtle emotion flickered across Seo Yuna’s face.

And then.

‘Huh?’

“Then I should join in too!”

Seo Yuna grinned mischievously and suddenly latched onto my other arm.

…?

I was startled.

But Kim Harin—

She was even more shocked.

Silence fell between us.

Kim Harin and Seo Yuna locked eyes.

And then—

“Hehe.”

Seo Yuna smiled calmly and linked arms with me as if it was the most natural thing in the world.

“Now we can all walk together, nice and close!”

Oh, shit.

I realized then—

This situation had taken a seriously wrong turn.

Seo Yuna was probably just messing around.

But Kim Harin’s expression was slowly shifting into something unreadable.

I squeezed my eyes shut.

‘Would I even make it through the night in one piece?’

Before I knew it, we had reached the school gates.

Since Kim Harin went to a different school, it was time to part ways.

Her school was about five minutes further from here.

I stood there, still on edge.

The strange tension hadn’t faded.

Seo Yuna, looking as cheerful as ever, turned to Kim Harin.

“Harin, you’re really cute! Let’s be friends!”

‘…That was the problem.’

‘Telling a yandere that you want to be friends?’

‘That was like pouring gasoline on an open flame.’

But Kim Harin only smiled quietly as she responded.

“Yes, me too.”

…?

‘She’s just letting it go like that?’

I glanced at Kim Harin.

With her usual gentle expression, she lightly brushed my sleeve and then took a step back.

“Then, see you at home, brother.”

“Huh?”

“It’s just a normal goodbye…”

‘So why does it feel so unsettling?’

Kim Harin softly stroked my arm one last time before quietly turning around and walking away.

I watched her retreating figure and took a deep breath.

‘…For now, it’s over.’

***

Seo Yuna giggled beside me.

“You and your sister are really close, huh? Unexpected.”

“Well, yeah.”

“If only you were that nice to everyone else.”

“They’re not family, so why would I?”

“Ohh, so if I call you ‘oppa,’ will you be nice to me too?”

“Don’t. That’s creepy.”

I shut that down immediately.

But Seo Yuna just laughed and playfully nudged my arm.

“By the way, Harin is seriously adorable. And so sweet.”

“…Is she?”

“Yeah. She’s nothing like you.”

“…Hey.”

“Yeah, I guess to everyone else, she must seem like the cutest, most lovable little sister.”

“It’s unfair. Seriously.”

We kept exchanging lighthearted banter as we walked through the school gates.

But—

For some reason, the back of my neck felt cold.

Kim Harin continued walking.

Even as she passed through the front gates of Hanbit Academy, she could still hear their voices from behind.

“Ohh, so if I call you ‘oppa,’ will you be nice to me too?”

Seo Yuna’s playful tone.

And—

“Don’t. That’s creepy.”

Kim Dohyun’s firm rejection.

A faint smirk lifted the corner of Kim Harin’s lips.

‘Well, that’s a relief.’

But she couldn’t be sure just yet.

Seo Yuna.

At first glance, she just seemed like a friendly, playful person.

But no one could ever truly know what lay beneath the surface.

‘Didn’t she say something like, “She’s nothing like you”?’

That wasn’t just a casual compliment.

From the very beginning, Seo Yuna had been acting way too familiar with Kim Dohyun.

That much was certain.

‘That sly fox definitely has feelings for my brother.’

So now… what should she do?

Kim Harin walked slowly, organizing her thoughts.

‘Was Seo Yuna really just a friend?’

‘Or… did Kim Dohyun have romantic feelings for her as well?’

If it was the latter—

She had to put a stop to it immediately.

Kim Harin gradually clenched her fists.

At first, it might just be simple friendship.

But over time, feelings could change.

And eventually—

***

“Harin, I know you rely on me, but it can be exhausting.”

“You can’t be so possessive.”

“I need to be able to live my own life too.”

That’s how it would start.

And then, one day—

He might leave her.

Kim Harin smiled quietly.

‘I’m the only one who can be by my brother’s side.’

‘We’re each other’s only family.’

‘He is my everything.’

‘And I have to be his everything too.’

But now—

If someone tries to take that away from her…

What should she do?

She had been carefully observing Seo Yuna today.

First.

At the beginning, she hadn’t been wary at all.

That was probably because she only saw Harin as “Dohyun’s little sister.”

Second.

Through their conversations, she tried to get closer.

She was playful on the surface, but it felt like she was testing Harin’s reactions.

Third.

She constantly made physical contact with Dohyun.

Linking arms, playfully nudging him—it was too frequent to be meaningless.

Fourth.

She reacted strangely when Harin showed affection toward Dohyun.

She did call Harin cute, but there was a sharp edge to her gaze.

Conclusion.

Seo Yuna has feelings for Dohyun.

This isn’t just friendship.

‘That sly fox. As I thought.’

Kim Harin took a slow, deep breath.

And then she held it in.

‘Calm down.’

Now isn’t the time to act recklessly.

There’s no need to rush.

For now, she’ll play along—gather information.

And gradually, she’ll make sure Seo Yuna’s feelings never develop any further.

She’ll limit their time alone together.

Going to school together.

Leaving school together.

If that fox ever tries to be alone with him… Harin will be there too.

The enemy must be kept under close watch.

By staying close and pretending to be friendly, she can stop Seo Yuna before she even has the chance.

She has to stay with Dohyun at all times.

So that he never pushes her away.

So that he never finds her annoying.

So that he realizes she’s the most important person in his life.

And finally—

If, despite everything, Seo Yuna still tries to cross the line…

Then—

Then, there will be no other choice.