My Childhood Friend Who is My Girlfriend was Stolen by My Best Friend. From Now on, I'll Flirt with My Ex-Best Friend's Little Sister! - Chapter 6

Mission Aborted?

Since homeroom is about to start, I return to my classroom.

As I sit in the front seat by the window, I see someone approaching me.

“Good morning, Toshiya.”

“…m-morning.”

That person is none other than my former best friend, Shintaro Nakajo.

Despite his glasses, his handsome features can be clearly seen.

His sharp and cold demeanour make him seem a bit unapproachable.

“What’s wrong? You don’t look very energetic today.”

“Eh? Ah, maybe it’s just because I didn’t get enough sleep last night.”

“You should get proper rest. Cutting down on sleep never leads to anything good.”

…whose fault do you think that is?

“Yeah, but I just can’t seem to fall asleep.”

“Hmm. Then let me teach you my recommended sleeping method.”

“Recommended sleeping method?”

“Yeah. Count Rinka.”

“Huh?”

“I said, count Rinka.”

I’m taken aback by his sudden absurd suggestion. My mouth is wide agape.

“It’s practically the same thing as counting sheep, but just replace the sheep with my little sister, Rinka. Many Rinkas will appear in your mind. There is nothing happier than that, right? Well, the downside of that is you’ll get so happy that you can’t fall asleep.”

“You’re still as crazy as ever…if Rinka-chan hears this, she’ll definitely get goosebumps, so don’t tell her about it.”

“That’s too late. I’ve mentioned it to her once before, and I was met with a full-on contemptuous glare and disdain. She didn’t speak to me for about two weeks. It’s hard enough not having any decent conversation as it is…Rinka’s tsundere attitude is really giving me a hard time.”

“That’s not exactly what you call a tsundere…”

His extreme sister complex is still as strong as ever.

Shintaro puts his middle finger on the bridge of his glasses and lifts them up.

“What’s with that reaction? I went out of my way to give you some good suggestion. Well, it must be because you’re all excited now that you’re dating Tsukimiya-san, right? You were probably chatting late into the night with her on the phone.”

“I wish that were the case…”

“Hmm?”

“No, it’s nothing. Ah, by the way, there is something I want to ask you, Shintaro.”

I force a smile and stare intently into his eyes.

“What is it?”

“What do you think about Airi?”

“What do I think of Tsukimiya-san? I mean, I see her as Toshiya’s girlfriend. She talks to me casually too. She seems like a bright and cute girl. Ah, but don’t worry, I’m focused solely on Rinka. I don’t have any romantic feelings for Tsukimiya-san.”

“I see.”

I can tell that he doesn’t understand the intention behind my question.

He seems confused by my sudden question.

As an awkward silence fall between us, Shintaro slightly raises the corners of his mouth.

“Well, as cute as she is, she can’t compete with Rinka.”

“You really are a sis-con, aren’t you?”

The bell rings.

Following that sound, the homeroom teacher enters the classroom.

“See you.”

Shintaro says so as he returns to his seat.

It’s the same morning routine as always.

But for some reason, it feels a little different this time.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

In the end, nothing particularly interesting happened today.

During class breaks, Airi came to my classroom, and we had a light chat. At lunchtime, we had lunch together.

I also chatted with Shintaro as usual. Objectively speaking, it’s just an ordinary day with nothing unusual.

However, I feel hollow inside. It’s as if there is a hole in my heart.

There were opportunities for Airi and Shintaro to interact, but there was nothing particularly unnatural about it.

The distance between them was the same as always, a typical distance between male and female friends.

But the scene I saw yesterday lingers in my mind, I can’t get it out of my head.

“—Hey! …Senpai, Senpai! Are you listening?”

“Ah, what was that again?”

While I’m spacing out, I feel a gentle poke on my cheek.

When I look up, I see Rinka-chan’s face right in front of me.

Right now, we are at my house.

Just like yesterday, we are sitting across from each other at the low table.

“We are in the middle of discussing how you and I can flirt without getting caught, aren’t we?”

“Ah right. We are talking about that.”

“Are you okay, Senpai?”

“I’m fine…yeah, I’m fine.”

“Shall we take a break? I can make something for us.”

“No, it’s really okay. I’m fine.”

I stop Rinka-chan as she tries to get up and head to the kitchen.

“But—”

“Hey…I know it sounds foolish, but can I ask you to hear me out for a while?”

After spending the day with Airi and Shintaro, I have some doubts.

“Sure. What is it?”

“I think what I saw yesterday might have been a misunderstanding. It was probably just someone who looked similar to Airi and Shintaro.”

“Eh?”

“Well, when I talked to them earlier today, there was no sign of anything like that. They didn’t seem like they are secretly dating behind my back at all.”

“W-What are you talking about, Senpai! I witnessed the cheating scene too! And there are some suspicious behaviours too! There is a high chance that they walk to school together in the morning, and they must have been secretly flirting with each other behind your back as well.”

Rinka-chan puts both of her hands on the table and try to reason with me.

She has a point. After all, I have seen the cheating scene with my very own eyes.

I know what I’m saying doesn’t make any sense at all. It’s purely an emotional thought.

“But can someone really lie so easily? I don’t think they were lying. I know it sounds foolish, but I’m starting to want to believe in them.”

“Senpai…”

“I’m sure it was just a mistake. They would never do something like that…I’m sorry, Rinka-chan, but about the revenge plan, I think we should abort it—”

“Please hold off on that decision. I have a proposal.”

Rinka-chan suddenly interrupted my words and said so.

“A proposal?”

“Yes. Let’s get some solid evidence of the affair.”

She leans forward, closing the distance between us.

“Being betrayed by someone close to you and not being able to accept that reality—it’s completely understandable. But this is not a problem that can be ignored. If we ignore it, you’ll end up getting hurt even more, Senpai…I know it’s tough, but I’ll be with you. So let’s face the reality.”

“Rinka-chan…”

“Alright, now that it’s decided, let’s act immediately. Shall we go now, Senpai?”

“Eh? It hasn’t been decided yet—wait, are we going now?”

Rinka-chan pulls on my arm.

“Of course. A detective doesn’t have time to rest.”

With a smile on her face, she leads me along.

With that, we decide to start gathering evidence of the affair.