I'm the Only One Who Doesn't Know My Sister is My "Stepsister" ~The Beautiful Twin Sisters Want to Seduce Their Oblivious Brother~ - 6

Chapter 6: Stepsisters Meeting

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I studied with Onii until 10 pm. After that, I took a bath and did my skincare routine in front of the bathroom sink mirror before returning to my room. I was usually a night owl, but studying this late was a first for me. So I was feeling really sleepy. I rubbed my tired eyes and reached for the hairdryer to dry my hair when Onee-chan, who was sitting at the study desk with her pajamas on, suddenly stood up. 

“Kairi, can I talk with you for a bit?”

“Hm? What’s up?”

“….”

The look on Onee-chan’s face made it clear she had something important to say. It was the same expression she had when she was about to give her speeches as the student council president during school assemblies. Sensing the serious mood, I placed my hairdryer back and sat down on the bed. 

“”Can I have a bit of your time?”

“Sure, I guess. But I’m really sleepy, so keep it short—”

“Alright, then, let’s start the ‘Stepsisters Meeting.'”

“…W-What?”

Out of nowhere, Onee-chan announced the start of ‘Stepsisters Meeting’, something I had only heard just now. She left me utterly dumbfounded.

“First, go sit in your chair so you won’t fall asleep.”

“O-Okay…?”

Doing as I was told, I moved from the bed to sit in the chair at my study desk. 

“And the topic of our discussion is… Of course, Onii-chan.”

“What do you mean by ‘of course’?”

“Kairi… You were having a lot of fun with Onii-chan just now, didn’t you?”

Onee-chan continued, disregarding my question.

“It’s been a while since I last saw you look that happy….”

“I-I wasn’t having fun or anything! I mean, I was studying!”

“…Liar.”

Every single word that escaped Onee-chan’s lips felt heavier than usual, causing me to feel uncomfortable. Could it be… She didn’t like the idea of me having a study session with Onii-chan in the living room earlier? But didn’t she just say she wasn’t a brocon yesterday?

“Hey, Kairi… You always tease me for being a brocon, but aren’t you just as much of a brocon as I am?”

“No-No! I just want to go to the same high school as him—”

“That’s exactly what being a brocon means!”

Onee-chan, who was usually so calm and composed, suddenly raised her voice at me. Seeing her acting like that, I was taken aback as well.

“Wha-What are you so angry about, Onee-chan? You’re scary. Do you really like Onii that much?”

“Yes.”

“But didn’t you just tell me yesterday that you’re not a brocon? You’re being contradictory.”

“…Then, Kairi. Here.”

Onee-chan then pulled something black out of her pajama pocket and handed it to me. 

“What is this? Shorts?”

“That’s Onii-chan’s freshly worn underwear.”

“UGH!!!”

The moment I realized that was Onii’s underwear, I immediately threw it on the floor. Just why the heck did she had Onii’s underwear with her?! I mean, I already felt a bad premonition the moment I caught a whiff of that weird smell that almost made me moan when she handed the underwear to me!

“Why did you give me that gross thing?!”

‘Fu… Fufu…”

“What’s with that creepy laugh now?”

“Kairi, your love for Onii-chan is still far from enough. You don’t even know how to enjoy Onii-chan’s underwear.”

“E-Enjoy…?”

Onee-chan picked up the underwear I had thrown on the floor and without any hesitation, she brought it close to her nose. 

“First, you savor the sweat that has soaked into the waistband. Inhale the scent of sweet from Onii-chan’s waist. Then, you enjoy the rich and pungent aroma from the outside. And finally, you turn them inside out and—”

“Huh?! Wa-Wait!! Onee-chan!! What are you doing?!”

“I’m merely enjoying Onii-chan’s underwear. Is it that hard for you to understand?”

“O-onee-chan, you’re so gross. I think I’m going to puke. U-Ugh…”

“Gross?! I-if you really love Onii-chan then this is a perfectly normal activity!! This much is normal!!!”

“O-Oeghhh…”

I gagged, but I still tried to curb the nauseous feeling that had risen from the back of my throat. Somehow, I managed to prevent myself from actually throwing up. 

“You… You were getting so cozy with Onii-chan in the living room and yet, you don’t understand something as basic as this. Mediocre. Absolutely mediocre.”

“I don’t want to understand that either!! Onee-chan, what you’re doing right now is beyond the line of a brocon!!”

Creeped out by Onee-chan’s behavior, I adjusted myself in the chair. 

“S-So? What is this about? Did you just want to brag about how extreme your brocon is?”

“No. Watching you and Onii-chan getting all cozy in the living room made me realize something.”

“Realize what…?”

“Kairi, you haven’t told Onii-chan about that, right?”

When she said ‘that’, I naturally thought about the fact that we were actually Onii’s stepsisters. 

“I haven’t told him, but… Would it be bad if I did?”

“Of course it would. You know how Onii-chan is still haunted by the trauma he went through in junior high, right?”

“You mean… When he was treated like a walking wallet by his girlfriend.”

Onee-chan nodded, affirming my suspicion silently. 

“Onii-chan has been carrying that trauma with him ever since then. I heard from a senior I knew from my cram school that went to the same high school as Onii-chan that he hardly ever talks to girls at school. Besides, you know he’s been obsessed with those 2D girls lately, right?”

“Umm.. You mean that V-tu something?”

“Yes. VTuber. The trauma from being betrayed by his ex-girlfriend is so heavy that Onii-chan has escaped into the world of 2D. So if he were to find out that we weren’t actually blood related… He will distance himself from us.”

“Distance from us…?”

Hearing that, I remembered the conversation I had with Onii. He did say that if he was a stranger, he wouldn’t dare to get close to a girl like me. 

“The main topic of this Stepsisters Meeting is to ensure neither of us will tell Onii-chan the truth.”

“But if we don’t, he will only look at us as his little sisters, won’t he?”

“And that’s why I have a proposal for that.”

Onee-chan narrowed her eyes slightly. 

“Let’s have a match between the two of us, Kairi.”

“A match?”

“Yes. Whoever succeeds in seducing Onii-chan first, gets to tell him the truth.”

Upon hearing Onee-chan’s proposal, I tilted my head to the side in confusion. 

“Se-Seduce him? What do you mean?”

“It’s simple. The one who can make Onii-chan say ‘I love you’ first is the winner. Once he says that, the winner gets to tell him the truth. Of course, it’s better if you tell him the truth right before taking his virginity.”

Onee-chan explained. Her eyes were lacking the usual honesty from her honor-student look. Her eyes were glazed. She had an enthralled expression on her face as she licked at the drool that threatened to spill from her lips. She looked like a predator, ready to devour her prey. 

“So? Are you in, Kairi?”

“….O-Okay.”

At that moment, I realized just how dangerous Onee-chan was. She really wanted to do… Umm… Le-Lewd stuff with Onii…. Everyone only saw her as the pure, soft-spoken beauty with long black hair. She was the graceful student council president at school, but it turned out, she had been hiding this wicked and twisted side of her. The intensity of the darkness hiding within her was beyond my expectation. Now that I came to know just how deep her obsession with Onii was, I decided that I had to protect Onii from this ravenous beast at all costs.

“And so, the Stepsisters Meeting has come to an end. We’re rivals from tomorrow on, Kairi.”

“…I understand.”

I truly never imagined discovering the truth would lead to something like this. However, I absolutely mustn’t lose to Onee-chan or Onii’s sake.

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