Loophole in the Promise
I let out a low groan. “Mmm… Juhyuk…?”
My big sister stirred in her sleep, eyes fluttering open as she called my name. My movements froze instantly. My entire body turned to stone. A cold sweat cascaded down my back like a waterfall. It felt like my heart had dropped straight to the floor with a heavy thud.
…She’s awake.
I turned toward her—slowly, excruciatingly slowly—like a poorly oiled robot creaking at every joint. She was still half-asleep, gazing at me with hazy, dreamy eyes. Her gaze lingered on my face for a moment before drifting downward, landing on the wide-open bedroom door.
Ah, he was just about to leave.
That was probably what she thought. But inside my head, an entirely different—and extremely optimistic—interpretation was blooming.
Yes. A promise is a promise. I firmly believe a man should keep his word. The promise had been: I won’t do anything while she’s sleeping.
But right now, my big sister was awake. That meant the premise of the promise no longer applied.
Oh thank you, God! This is completely legal! It’s self-defense! It’s her fault for seducing me with that defenseless posture, not mine!
I cheered inwardly and launched into a flawless performance. The sleazy grin vanished in an instant, replaced by the most worried little-brother expression in the world.
“Noona, you’re awake? I came because I had something to tell you… but you were sleeping, so I was about to head out.”
Still drowsy, she rubbed her eyes at the sound of my concerned voice and asked, “Something to tell me…?”
She still had no idea what kind of position she’d been sleeping in. I sat down on the edge of the bed, staring openly at the space between her spread legs—right at the pink strawberry-patterned panties—and said,
“Yeah. But… Noona, the way you were sleeping was so bold… I completely forgot what I was going to say.”
At my blatant gaze, she finally realized her posture. Her eyes traveled downward. The moment she saw her own widely spread legs and the panties nestled between them—
“Hiiik!”
She let out a sound that was almost a scream, her face flushing bright red in utter shock. In a panic, she snapped her legs shut. Overwhelmed by extreme embarrassment, she yanked the blanket over her head all the way to the top, like an ostrich burying its head in the sand.
But I had no intention of letting her escape. I grabbed the blanket, preventing her from completing her perfect hiding maneuver.
“Wait a second, Noona.”
A muffled voice came from under the covers. “…Go away.”
“No way. Noona, sleeping like that… honestly, that’s foul play. When a guy sees something like that, it’s really hard to think rationally.”
I started my victim cosplay, sounding as wronged as possible. “So you have to take responsibility.”
“W-what do you mean, responsibility…” Her voice from inside the blanket was practically whimpering.
I gently stroked her closed thighs over the blanket and said, “We’ve already used your hands, your mouth, and your breasts. But we haven’t used this spot yet.”
When my fingers tickled the soft flesh on the inside of her thigh, her body twitched hard beneath the blanket.
“W-what would you even… do with here…?”
I grinned and explained it to her in the kindest teacher voice on the planet. “It’s simple. You just need to squeeze your legs together like this.”
I demonstrated by gently prying her thighs apart and then closing them again. “I’ll just rub between them. I’ll take care of the rest. Isn’t this the easiest option?”
The suggestion sounded almost merciful at first glance—just rubbing between them. There was a brief silence under the blanket. Then, little by little, the strength drained from her grip on the fabric.
I half-forced, half-gently overpowered her resistance. She kept the blanket pulled up only to her face now, eyes squeezed tightly shut.
Fuck, covering just her face makes it even hotter…?
I spread her legs, then positioned myself right on top of the pink strawberry-patterned panties.
“J-Juhyuk… that’s… that’s not my thigh…”
“Huh? Oh, I slid down a bit. Got it.”
I repositioned myself firmly between her plump, luscious thighs and clamped them shut, locking myself in place. Finally, I began to move my hips—slowly, ever so slowly.
This is insane…!
It was a completely new dimension of sensation, nothing like anything before.
Fuck…! The pressure is on par with those massive ‘divine tits’ of hers…!
Through a single thin layer of cotton panties, I could feel the soft, yielding flesh and scorching heat. My poor junior was being rubbed against the thick, meaty part of her thighs while desperately trying to hold back. Heaven was right in front of me, yet I couldn’t enter. That agonizing closeness was driving me crazy.
Damn it…! What kind of paradise is waiting just beyond those panties?!
I gradually picked up speed. With every thrust, her soft thigh flesh squeezed and clung to me with delicious elasticity.
Should I slide down just a little more? It should be fine, right?
My rationality was already on the verge of total shutdown. While performing the act, I slowly began inching my junior toward her panties. I felt her flinch, but I kept moving my hips as if nothing was wrong.
My creeping junior eventually succeeded in feeling the texture of the fabric. I continued thrusting back and forth, savoring the slightly rough sensation of the panties.
…It feels a little slippery now?
What had been hot and full of friction was now moving smoothly. A sense of déjà vu hit me, so I looked down.
…! She’s wet! She’s definitely wet!
The color of her panties was darkening in a clear, damp patch. The sight made me rock my hips with even more passion.
Noona trembled all over as she felt her most sensitive area being pressed and rubbed through the soaked fabric by something hot and hard. The intense friction, the heat against her precious spot, and my ragged breathing were all paralyzing her reason.
Before she knew it, soft moans began slipping from her lips.
“Hah… mmh… ngh…”
Those moans snapped the last thread of my remaining sanity. In the end, I released everything onto her strawberry-patterned panties, her thighs, and her lower belly.
The drenched pink panties looked more obscene and immoral than any naked body could have.
“Haa… haa…”
After finishing, I gently brought over some wet wipes and meticulously cleaned her body and the thoroughly soaked panties. She was still reeling from the shock and arousal, breathing hard.
Looking at her like that, I thought,
Wow… this is seriously the best. I thought those H-cup breasts were a gift from God, but these thighs are national-treasure level too. Is she actually a succubus sent by the heavens? And I’m just a toy in her hands?
I softly stroked the still-warm, tender flesh on the inside of her thighs and praised her in a deeply satisfied voice.
“Noona, that felt incredible. Your breasts are so soft and amazing, but your thighs are just as good, huh?”
At my shameless compliment, the tips of her ears—peeking out from under the blanket—flared bright red. I smiled in satisfaction and stood up.
Just before leaving the room, I delivered one final killing blow.
“I’ll be asking for this again, Noona.”
That single sentence meant that ‘thigh jobs’ had just been officially added to the menu of our secret nighttime rituals.
When I returned to my own room and closed the door, I immediately collapsed to the floor. My heart was pounding like crazy, and my legs had turned to jelly. A massive wave of self-loathing crashed over me moments later.
I smacked myself in the head.
You crazy bastard! Kang Juhyuk, you insane motherfucker!
What had I sworn to myself just a few hours ago? Hadn’t I acted all noble, saying I’d keep the line and never commit social suicide?
And what was the result? One look at Noona’s spread M-shaped legs and every single resolution and scrap of reason I had vanished like dust.
In the end, I was nothing but a slave to my own dick.
Yeah… let’s empty our head. Don’t think about anything.
To shake off the guilt, I turned on the computer. Without thinking, I clicked back into the community post that had given me salvation that morning.
A few more comments had been added since then.
I couldn’t tell how much was true. Honestly, 99.9% of it was probably just these lunatics flexing. But none of that mattered to me right now.
My happiness circuit had already started running at 300 km/h.
See! This is the world! I’m not the only one! If anything, I’m actually one of the better ones! That ‘LittleSisterTamer’ guy is complete garbage! Compared to him, I’m practically a gentleman!
Before I knew it, I was nodding along, deeply empathizing with every comment.
Yeah, fuck it. I’m not the crazy one. The world is crazy. I’m just following the natural order of things. This is an unstoppable fate.
I completed yet another perfect mental victory. The self-loathing vanished without a trace. In its place burned a new determination to completely conquer my big sister.
If this is a world where only crazy people are normal, then I’ll gladly become crazy too…!
Of course, the world was functioning perfectly normally. The only crazy one was Kang Juhyuk.