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 7

Affair Investigation Begins

“No results again today…”

It has been three days since we decided to gather evidence of Airi’s affair with Shintaro.

We have tried to gather evidence during various times, such as when going to school in the morning and after school, but there have been no results so far.

Now, I’m sitting across the low table from Rinka-chan in my room.

“Ah, I guess what I saw was just a mistake.”

“That’s not true, Senpai. I saw it with my own eyes.”

“But in the end, we weren’t able to get any evidence of them having an affair. We did see them walking to school together this morning…but they weren’t flirting with each other or anything like that, they kept a friendly distance between them. Other friends also joined them along the way, so they didn’t really spend that much time alone together.”

“That may be true, but at least people know that you and Tsukimiya-san are dating. They can’t take the risk to flirt with each other while walking to school, especially with others around.”

“That’s true, but…they also didn’t talk to each other at all after school.”

“…that’s true, but.”

Three days have passed since we started the investigation of their affair.

We haven’t been able to get any solid evidence. On the contrary, the cheating scene I witnessed that day has been imprinted in my mind as a mistake.

“It seems that I’m going to try to believe in them after all. I can’t imagine Airi betraying me, and neither can I imagine Shintaro doing that. We’ve known each other since middle school. There is no way that guy who is really obsessed with Rinka-chan would do something like that.”

“Senpai…”

Rinka-chan looks at me with sad eyes.

Her voice is quiet, as if it’s about to fade away.

“…so, are you going to continue dating that person? And you are going to keep being friends with my brother?”

“Well…”

“I don’t want that. I absolutely don’t what that. Why don’t we try a little longer? It’s only been three days. It’s too early to give up.”

“Rinka-chan…”

Her teary eyes look like they’re about to burst into tears ay any moment, but she is acting strong as she holds my hands tightly.

I really am no good…I’m too weak-hearted. I want to run away at the first opportunity.

If Rinka-chan wasn’t pulling me along, I would just look for the easy way out.

It’s easy to pretend not to see the reality.

I tell myself whatever convenient excuse I can come up with and block out any information I don’t want to know.

While it might be easy to do so, but in the end, I know that it will slowly strangle me.

“Plus, I should tell you, even if you quit, I have no intention of quitting! I’m determined to gather evidence no matter what!”

I wonder if there’s anyone else out there who would go this far for me.

With a slight smile, I mutter softly.

“…I should’ve just gone out with Rinka-chan from the beginning…”

“Eh?”

“Ah, n-no, it’s nothing!”

I didn’t mean to say it out loud, but it seems to have slipped out of my mind.

In an instant, Rinka’s face turns red.

Seeing her like that, my face starts to turn red as well.

A heavy silence fills the small room.

Neither of us can look up at each other. We both just stare down at the floor.

“…Senpai, do you still like Tsukimiya-san?”

“Yeah.”

I’ve had this unrequited love for over six years now.

It’s not the kind of feeling that can be so easily forgotten.

“Then, it seems that I really can’t quit here after all. I want Senpai to get over your feelings for Tsukimiya-san. Then, I’ll proudly declare myself as your girlfriend. So for that reason, I want you to face the reality!”

“Yeah, you’re right. I’m sorry, Rinka-chan. I think I have a habit of running away.”

“It’s okay. I’ll lead you along properly.”

Rinka-chan tightly clenches her hands, showing her determination.

Then, she stands up and says,

“That’s settled then! We’ll continue the investigation tomorrow, Senpai!”

“Wait! I can’t do it tomorrow.”

“W-What do you mean? Am I going to be rejected after this turn of events!?”

“N-No! It’s not like that! I have a part-time job tomorrow. You know, my family runs a wagashi shop, right? As a condition of living alone, I have to work at least twice a week.”

(TN: ‘wagashi’ is a traditional Japanese sweet made of mochi, anko, and fruit.)

I crush Rinka’s enthusiasm just as she is getting fired up.

She looks at me with teary eyes and comes closer.

I hurriedly start to explain to Rinka-chan that Friday is usually a very busy day.

“There will be a lot of customers, so that’s why I have to work part-time.”

“Part-time job…yes, that’s it, Senpai!”

“Huh?”

“Does Tsukimiya-san know about your part-time job days?”

“Yeah, she knows about it.”

Airi often ask about my shifts, and sometimes she even works part-time in my parents’ shop as well.

Rinka-chan’s eyes sparkle as she begins to deduce like a detective.

“Senpai, could it be that you finished your part-time job early last Friday?”

“Yeah, we had a customer who bought a lot of stuff. We ran out of sweets, so we closed up the shop early.”

“Is it rare for your part-time job to end early?”

“Yeah, even after my shift ends, I often spend time with my parents.”

“That’s pretty much confirmed, then. While you’re working, those two are probably having an affair behind your back.”

Rinka-chan’s deduction indeed makes sense.

“So, if that’s the case, tomorrow is our chance to gather evidence?”

“Yes, that’s right! Leave it to me, Senpai. I will definitely take pictures of the cheating scene tomorrow.”

“Wait. If that’s the case, I’ll go too.”

“But, Senpai, you have your part-time job.”

“That’s fine. In the end, the reason why I have to go to my part-time job is just because my mom is worried and wants to see my face. I can reschedule for another day.”

“I see.”

And so, the time passes and tomorrow arrives.

After school.

“Toshi-kun. You have your part-time job today, right? Let’s go home together.”

“Yeah, that’s right. Let’s go.”

I head home with Airi.

I managed to reschedule my part-time job to another day, but I keep that a secret from Airi.

Now, it’s time to secure the evidence of their affair once and for all.