The Worst Day of My Life

My girlfriend is stolen by the guy who I thought is my best friend.

Well, ‘stolen’…that word might be a bit presumptive.

I just happened to see them.

On my way back from work, I saw my best friend and my girlfriend coming out of a hotel together.

They looked really close with each other, walking arm in arm like a couple.

In a voice I have never heard before, my girlfriend called his name sweetly and kissed him.

It’s so obvious that she is cheating on me.

I want to believe it’s just a dream or something.

I don’t know how far they’ve gone, and to be honest, I don’t want to know.

But one thing is certain, my girlfriend is cheating on me…and the person she is cheating with is my best friend.

A kiss…even I haven’t kissed her yet…

“Hah…”

I let out a heavy sigh.

Along with that sigh, I feel like my soul is being drained out of me.

Curled up in the corner of my room, I’m overwhelmed with the urge to disappear from this world.

I never imagined that I would be cheated on.

My childhood friend is my first-ever girlfriend, someone I’ve known since I was little…I’ve always loved her for such a long time.

With the support of my best friend, we finally became a couple.

After all that struggle to make my childhood friend mine, I thought I can now enjoy a happy youth.

But…what the hell is this?

It’s only been three weeks since we started dating.

It’s not like we often fight or anything like that.

I thought we are progressing well as a couple. But apparently, I’m the only one who thought it that way.

“I’ve never seen my childhood friend make a face like that before…”

I mutter absentmindedly, staring up at the white ceiling.

Maybe they have been dating each other even before she started dating me.

Did she decide to date me just for fun? Or maybe it’s out of pity?

Perhaps, it’s all just to make me a laughingstock.

No matter how much I think about it, I can’t come to any conclusion.

But whatever the reason, it’s not something pleasant.

I’m toyed with.

No matter what happens, that fact will never change—

My childhood friend and my best friend.

If they have been genuinely dating, I honestly would congratulate them.

I’m sure that I could’ve suppressed my jealousy and still wished for their happiness.

But…this is just too much──

“This is too cruel.”

Sitting with my knees up, I bury my face.

I no longer have the confidence to face either of them.

I don’t think I can speak to them anymore. Our relationship is over.

…this is truly the worst day of my life.

─ding-dong.

The doorbell rings.

I must seem really depressed right now.

I currently live alone.

There is no one else in the house besides me.

I have no choice but to answer the doorbell, but…I just don’t have the energy to get up right now.

─ding-dong.

I don’t know who it is, but I’m sorry.

I’ll just pretend I’m not home.

─ding-dong.

“……”

─ding-dong.

─ding-dong.

─ding-dong.

─ding-dong.

“T-They’re really persistent…”

The doorbell keeps ringing.

I was actually planning to pretend I’m not home, but they’re being quite persistent.

So, I reluctantly get up and head to the front door.

With a click, I open the front door.

Then, the person standing at the entrance is…

“Rinka-chan?”

She has light brown hair tied up in a side ponytail on the left side of her head.

Her facial features are neat, and her skin is so pale that it’s a bit worrying.

She’s a bit shorter than girls her age, but because of that, her breasts looked quite developed, accentuating highlighting her feminine curves.

She’s a year younger than me, currently a first-year high school student.

More importantly, she is my best friend’s younger sister—no, former best friend.

“Good evening, senpai. You look even more depressed than usual.”

The moment she sees my face, she immediately throws out a light insult.

I’m not in the mood for this at all. I’m feeling really depressed.

Normally, I would just brush off such comments, but right now, her words piss me off.

“Can you go home?”

“No. I can’t just leave you like this.”

“Hah?”

“Can I come in? My body is freezing.”

It’s already November. It must be freezing cold at this time of day when the sky is already dark.

When I take a closer look at her, Rinka-chan’s hands are indeed red and trembling.

I can’t figure out the purpose of her visit, but I decide to welcome her into my room anyway.

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

Sitting across from Rinka-chan, we face each other.

“Senpai, I want a glass of warm lemon tea.”

“I don’t have anything fancy like that. If you don’t want to drink it, that’s fine.”

“No, I’ll have it. Since Senpai made it for me.”

She takes the cup of barley tea from me and sips it slowly.

After quenching my thirst, I decided to get straight to the point and ask her the reason of her visit.

“So, is there something you need from me? Why did you suddenly come to visit me at this time of day?”

“Well, it’s more like I’m worried about how you’re doing, Senpai.”

“Worried about me?”

“Yes. You tend to overthink things on your own, don’t you? So, I’m worried that you might get depressed and just disappear without talking to anyone.”

There’s a part of me that resonates with her words.

Well, I just found out that my girlfriend is cheating on me, and I’m feeling terribly down because of it.

Could it be that she also found out about my girlfriend’s affair with her brother?

“Did you happen to see it too, Rinka-chan?”

“To be exact, I saw Senpai walking earlier, looking really depressed. Then I found out that Senpai’s girlfriend is having an affair with my brother…”

“So that’s what happened.”

“Honestly…it’s just unbelievable, isn’t it…?”

Rinka-chan murmurs so, gripping her skirt tightly.

She lowers her gaze, supressing her irritation.

Seeing her like that, I can’t help but lower my gaze as well.

The atmosphere feels really heavy.

“…Senpai.”

“Hmm?”

“Do you hold any resentment toward your girlfriend or my brother?”

“…well, I know this is not a good feeling to hold onto, but yes, I do have those feelings.”

“I’m glad to hear that.”

Rinka-chan’s dark expression shifts to a bright smile.

Not understanding the intent behind her words, I tilt my head slightly.

“You’re glad?”

“Yes, I was worried you’d say you didn’t resent them. I was worried that you might say something saintly like, ‘I want them to be happy’ or something like that.”

Rinka-chan is staring right into my eyes.

She takes my hands, and hold them gently.

“Senpai, are you really okay with them having an affair on your back?”

“…of course I’m not okay with it. But there’s nothing I can do about it.”

“You can do something about it. I’m here for you. Let’s get back at them!”

“Get back at them? How do you plan to do that?”

I ask so dumbfoundedly.

Then, Rinka-chan grips my hands tighter.

“I’ll become your cheating partner, Senpai. Let’s teach those guys how painful it is to be cuckolded.”