The Sound of Victory and Defeat

The sound of a phone being placed down didn't echo through the speaker. Seo Woojin’s phone seemed to be just far enough away that it couldn't pick up such quiet noises. But even without hearing it, I could easily visualize exactly what was happening on the other side.

—"Ahem, ahem...! H-here, come here. ...I’ll put it on for you."

—"I’m right in front of you."

—"I-I just meant...! ...Hic..."

Lee Hayoon, who had just sent me a frantic text, was now... no, my sister was putting her phone down and starting to fiddle with a condom wrapper. She pulled out a condom that looked just like a vitamin, and as it was held out in front of her sister’s... no, in front of Seo Woojin’s cock, she carefully rolled it on. She wanted to be fucked by that cock all night long without having to worry about getting pregnant.

—"T-there, uh, um... I, I think that’s it..."

—"It’s on right, so... ...now lie down properly."

There was a brief silence, followed by the sound of rustling as they shifted their bodies. Even though I was busy masturbating, the scene on the other side of the line was vivid in my mind.

—"Hey, hey...! It hurts...!"

—"You use your body every day, how does this hurt?"

—"Flexibility is a different issue from that... Ugh..."

My sister, stiff as a board because it was her first time. Seo Woojin pushed her thighs apart firmly.

—"Ugh... seriously..."

Too embarrassed, my sister covered her face with her arms. Instead of forcing her arms away to look at her expression, Seo Woojin simply rested his cock on her lower abdomen, just like he used to do with me.

—"...Wow, whoa..."

Her thighs trembled, and eventually, she lowered her arms slightly to peek at what was happening below. Seo Woojin had smeared plenty of lubricant on the condom over the panties she’d bunched up right next to her entrance.

—"Nngh... Ugh..."

—"Relax. It’s hard to put it in if you’re that tense."

—"I-I’m not tense... wait... it hurts..."

—"It’s okay. It’s normal for it to hurt... ...just endure it."

—"You’re so irresponsible, just telling me to endure it... Ah..."

—"...You get hurt often, so you should be used to the pain to some extent."

—"That’s... true, but..."

Seo Woojin began to tame my sister’s virgin pussy, which was tense from the first penetration. The image of the two of them was burned into my brain. Well, in reality, the only thing certain was that I was the one lying on my bed, busy scratching at my own vaginal walls along with those delusions. It’s fun, isn't it? These kinds of fantasies. ...And it’s a turn-on, too.

—"...That’s half-way for now. ...How is it? Are you okay?"

—"I’m, okay..."

—"You said it hurt earlier. Are you really okay?"

—"...If I say I’m not, are you going to stop...?"

—"For now."

—"...Then, I’m okay..."

—"..."

—"You, you can fuck me however you want... you idiot..."

I thought her voice sounded a bit cute, but my sister, whose voice I usually hated because it was always full of nagging, had completely changed into something full of *aegyo* in front of Seo Woojin. She sounded much more like a younger sister than an older one. ...And a younger sister who was a ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠ball of pure sexual desire, at that.

—"However I want?"

—"..."

—"Then is it okay if I fuck you all the way to the root?"

—"...U-un..."

Heh heh... Lee Hayoon, you crazy bitch. She said it’s okay to fuck her to the root. If I remember correctly, his is easily over 20cm. She must have no sense of reality from watching too many videos of guys with huge cocks. If she gets properly fucked by that all night, how is she going to go to the Academy tomorrow? What, is she planning to declare a personal holiday? Making up some excuse like she suddenly got sick?

But what a shame. There’s a *Healing-type* transcendental on campus, so that excuse will never work. ...Though if she showed up to class with her neck covered in hickeys, everyone would just whisper, "Looks like she was getting laid all night."

—"If I go too deep, it’ll hurt even more than now."

—"Th-that time with you... Ugh..."

—"Pfft..."

That time, she said. Just as the aimless chatter stopped, the sound of wet, sloppy kissing began to echo again. And, amidst the sweet sound of kissing...

—"Nngh... *slurp*... H-huff...!"

The sound of wet, slick flesh meeting, the sound of air escaping between their lips—it leaked through the phone speaker and tickled my eardrums. ...Is Seo Woojin really fucking her to the root? Is my sister really making those strange breathing sounds because of it?

—"Nng... *haa*... Se-Seo Woojin... stop the kissing..."

—"...Is it hard? Breathing?"

—"Un..."

My sister’s voice, full of *aegyo* that I’d never hear between sisters, flowed through the speakerphone and filled the room. It felt like... like the two of them were having sex right next to me. Or like I was hiding somewhere, peeping at them. It was a very strange feeling.

—"...At least you’re not saying it hurts anymore."

—"..."

Lost in that strange feeling, I stopped lying on my stomach and turned onto my side, busily touching myself all over. Would Seo Woojin have treated me as tenderly if it were me there? If it were me, wouldn't I already be getting fucked like an animal, just the way my sister likes it? Doesn't that mean I’m even more turned on? While I was lost in my own delusions, I was just... masturbating to victory.

—"Wait... Ah, ugh..."

Perhaps he pulled her body toward him, because a sharp friction sound squeaked out. It wasn't just wet squelching anymore; it was *thwack, thwack, thwack, thwack*. The sound of sex began to fill my room, loud and clear. *Ngh-eek...* My sister’s lewd moans, struggling to escape from between her gritted teeth. With all of that in my ears, I folded one leg up, spread it wide, and rubbed my fingertips against my vaginal walls, which were already so sore from coming that they felt numb.

—"...Hayoon. Stop covering your face."

—"H-how can I not cover it...! Because of you, because of you..."

—"Whether you’re crying, laughing, or falling apart, whatever expression you make, I’ll be turned on, so put your arms down."

—"No... I’m, I’m embarrassed... *Kyaaak*...!"

—"...Ah. Fuck."

—"..."

—"..."

—"Hie... ...Ugh. Wa-wait... That’s too violent..."

Why? Sister, what kind of expression were you making? Why did the sound of him slamming his cock into you get so much faster than before? ...Why have you been letting out such strange moans since a moment ago?

I squeezed my nipples, which had become hard enough to give me chills, and hurriedly looked at the mirror in the corner of the room. Unfortunately, I couldn't see my face from this angle, so I stumbled up, flopped down onto the bed upside down, and took a peek. My face, finally visible, was a mess—tears as if I’d been crying, a flush as if I were embarrassed, and an expression of pure pleasure as if it felt good.

—"Mouth. Open it wider."

—"Hee...? Heh...?"

—"Not just sticking the tip of your tongue out and panting, open it properly."

—"...Ah..."

The subtle tenderness I’d felt from the start was gone. Now, his voice was thick with pure, unadulterated lust. After the sound of my sister opening her mouth and saying "Ah...", all sound stopped for a brief moment. ...I don't know what they were doing, but it sounded like I heard a gulping sound several times, but... *slurp*... *slurp*... Hearing the sound of them fucking while kissing sloppily, it seemed my sister had done something else ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠to turn his cock on.

—"...Phaaa... Hey, Woojin... Woojin-ah..."

—"Why."

—"Sister, I’ve come too many times... My head is completely blank right now... Wait a second, let’s rest..."

—"...How many times did you come?"

—"Five, no, six... ...Nngh... Seven..."

—"..."

—"Stop fucking me already...! Listen to me..."

—"I’m this hard, how can I rest now?"

—"Even so... I can’t even speak properly right now..."

The sound of him slamming into her pussy completely drowned out my sister’s voice, torturing my phone speaker. The cute, lewd moans that followed were buried under the lewd sounds of sex. Did I... did I get treated like that by Seo Woojin, too? Recalling the memory of us having sex like animals on the desk... recalling the memory of me moaning to my heart’s content only after I’d frozen and smashed my headphones... I was so excited that my brain felt like it was burning. I forgot that I’d even pressed the "Mute" button, and with my hand doing nothing to muffle my moans, I rubbed my clitoris like a madwoman, spraying my fluids all over the already soaked ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠towel.

—"I came, I’m, I’m coming again..."

—"I know. I can feel your inner walls twitching like crazy."

—"Th-then why did you ask earlier...!"

—"...Because it’s more of a turn-on to hear it directly from a woman. You idiot."

—"Ugh... D-don't tell me you’re making me call you *Oppa*..."

—"It’s a bit different, but... something like that."

—"You... pervert...! You total pervert...!"

Even though my sister and Seo Woojin ‍‍‌‌⁠​​⁠‌​​‍​​‍​‌​⁠‍‌‍⁠⁠‌⁠‌‍‌‍‌‌‌‍⁠​‌​‌​‌‍‌‌‌⁠‍​​‌‍⁠‌‌⁠⁠were taking a breather and talking, I couldn't hear a thing. *Squelch, squelch... squelch.* I was so deep into masturbating that nothing else mattered.

—"You, who usually acts like a big sister and holds your head high, it’s such a turn-on when you stammer and call me *Oppa*."

—"Wh-what’s so turning on about that...! Just, uh? Ask me to do a... a blowjob or something...!"

—"Is it that you don't like calling me *Oppa*?"

—"...It’s not that I hate it, but..."

—"Then use it when the time is right. ...Like when you want me to cum."

—"Cu-cum..."

—"I told you. It turns me on so much when you stammer in formal speech."

—"A-alright. I get it, so stop looking down at me and saying I’m turned on...!"

Until my vision went black. Until I couldn't think of anything. I buried my face in the soft duvet, choking off my own breath, and continued my lewd, thrilling masturbation. ...I don't think I’ve ever masturbated for this long, but this call... shouldn't I have recorded it to use later? It’s not like another chance like this will come along.

—"...O-Oppa..."

—"..."

—"...Cum inside Hayoon, as much as you want... Cum... Nngh..."

Will I be able to have another "sex practice" with Seo Woojin? Thinking that, *squelch, squelch...* *Splurt, splurt.*

—"Huff... *Haa*... ...You crazy, bastard... Stop cumming..."

—"It’s okay. The condom won't burst from something like this."

—"Not that...! The, the condom is getting so full it keeps hitting my uterus..."

—"..."

—"...F-fine, whatever...!"

I pulled my fluid-covered fingers out from where they’d been scratching my walls, turned my back to the phone, and panted heavily. The "victory masturbation" I’d told myself I was doing after stealing my sister’s boyfriend first. Now that I thought about it, it felt more like a "defeat masturbation." ...Since Seo Woojin had achieved his goal, I probably wouldn't be having sex with him anymore. Since my secret, shameful hobby seemed to be coming to an end. I just kept exhaling hazy, defeated breaths...

"......"

...Wait. Why would it end here? How to meet Seo Woojin without my sister knowing. And how to have even wetter sex than my sister. I still have that.

As long as I keep sending texts like this, I can have secret affair-sex with him whenever I want. As long as Seo Woojin doesn't refuse...