This Is Your Punishment
Even as our eyes met, Yuzuki’s mischievous footplay showed no signs of stopping.
I made sure Luna was still in the kitchen, then whispered to Yuzuki in the smallest voice I could manage.
“Yuzuki… what do you think you’re doing?”
At that, Yuzuki slowly tilted her head. With her eyelids half-lowered, she fixed me with a gaze like a playful cat, then cocked her head and smiled.
That smile blended innocence with harmless mischief.
“What do you mean?”
“I mean…”
My words trailed off at her innocent question. Her inscrutable attitude left my mouth dry and my tongue tied.
Even now, the tip of Yuzuki’s foot slid along my thigh with growing boldness. It flexed with finger-like dexterity, pressing and brushing against my groin.
A light press, a release, then another firm squeeze.
The friction traveling through her stockings and the fabric grew more cunning with every repetition. My back arched on its own, toes curling tight.
Finally, I forced the words out again.
“…Yuzuki. Stop.”
“Stop what?”
“The little game you’re playing. Luna’s right there. What if she catches us?”
“Hmph.”
Yuzuki answered with action instead of words. She curled her toes as if gripping me and pressed squarely against my crotch, rejecting my protest.
“Luna’s allowed to mess around, but I’m not?”
“No… that’s not what I—”
“Or is it only good when Luna does it?”
Her eyes trembled with the words. Beyond her lashes, suppressed emotions rose to the surface.
Resentment. Jealousy. Hurt. And woven between them, an unabashed flood of affection for me.
With her gaze lowered, Yuzuki slowly added more weight to her foot, conveying her feelings through action rather than words.
“…This is your fault, brother. You started it.”
“…Yuzuki?”
“You promised me. You said that even if the research made you fool around, you wouldn’t complain, but at home you’d only look at me… You agreed to that.”
Her voice was low, yet heavy with emotion.
“So what was this morning? When that girl climbed on top of you, you were practically drooling…”
Even as she spoke, Yuzuki bit her lip. The look on her face ran deeper than anger—it was raw betrayal and jealousy.
The foot still nestled between my thighs felt light in weight, but the emotion it carried was crushing.
The prank Luna had pulled on me that morning had been eating at Yuzuki ever since.
“Ugh…”
Suddenly, Yuzuki’s foot grew far more insistent.
The pressure that had been rubbing my center gained weight and rhythm, bearing down like a proper punishment. I unconsciously dragged my chair back and let out a short, sharp breath.
“So this is your punishment… You’re the one who messed up first…”
Her flushed cheeks and tightly sealed lips spoke of dissatisfaction.
Yuzuki’s voice remained soft, but a clumsy, lingering grudge seeped through it.
And because it looked so lovable to me, I could only stare at her in silence.
“…Didn’t I tell you? At home… I’ll do whatever I want.”
“But… Luna’s right here in the house right now…”
“Shut up. You’re the one who broke the promise, so don’t make excuses while you’re being punished.”
Yuzuki’s tone was firm. At the same time, she added another short, sharp press with the tip of her foot.
It didn’t hurt. If anything, it felt maddeningly ticklish. Maybe because I could sense the jealousy and affection tangled together.
“And honestly… why have you been doing nothing all this time, brother?”
“…Doing nothing?”
“Why won’t you do anything to me…?”
For a second I couldn’t process what she meant. It was far too direct for Yuzuki.
“From the very first day of Coupling you mixed your body with Luna’s… so why do you leave me alone? We’re always within arm’s reach the moment we open our eyes. We live together. So why… why won’t you touch me?”
The longer she spoke, the sharper her gaze became.
I felt a pang of unfairness. Her mood had been off for days, so I’d been trying to cheer her up. In that situation, how was I supposed to—
“That’s because you seemed upset lately, ngh—!”
“I said no excuses…!”
Her foot pressed against my groin again. This time she pinned it firmly in place so I couldn’t escape.
“…This makes me look like an idiot for waiting up every night.”
Lips pressed tight, Yuzuki finally added, voice nearly breaking.
“I even changed into my prettiest underwear on purpose… I lay in bed first… but you always just fall asleep…”
The tremor in her final words held more than anger. Yuzuki was wounded by the realization that she had been ignored.
“And now this… Luna suddenly waltzes into the house like she owns it…”
Jealousy and rage mixed in her voice, creating a resentful echo. Just then, Luna’s voice drifted from the kitchen—the one I’d thought was taking far too long.
“Hey, is there any ice in the fridge?”
Ice? In the morning?
There probably wasn’t any. While I stayed frozen, unable to speak because of the situation, Yuzuki’s eyes narrowed into cold slits.
“I don’t know. No one in this house has a weird habit of eating ice first thing in the morning like you.”
From the kitchen came Luna’s disappointed murmur in reply.
And at the same time—
“Ugh…”
Yuzuki’s foot, which had paused, began moving again.
The pressure against my groin was sharp and deliberate, like a honed blade of emotion. It felt as though she were pouring all her jealousy toward Luna onto me as punishment.
My hips twitched involuntarily. Not from pain—the opposite.
Yuzuki didn’t miss it.
She rubbed the tip of her foot lightly, toes curling and uncurling, as if testing me or trying to burrow deeper.
“Hmm…? Brother, you’re getting hard…?”
The eyes that had been frozen with cold anger only moments ago now burned with heat.
A delighted smile curved her previously tight lips. Her eyelids drooped halfway, shining with lewd satisfaction.
“Why? Does it feel good when I do this?”
Rub, rub— Her foot eased the pressure slightly, stroking me softly. It felt like a threat demanding I admit it.
“Getting excited by your little sister’s foot… You really are a pervert, brother. At this rate it stops being a punishment and turns into a reward, doesn’t it?”
She whispered with a quiet chuckle, eyes smiling playfully.
Yuzuki was savoring my reaction, clearly pleased with the result she had created.
Then the other foot that had stayed still began to move as well.
Its tip naturally approached, stroking my side before both feet crossed and intertwined, creating layered friction.
They pressed and squeezed my groin with clever precision.
“How’s that…? Feels better than before, right? You’re getting excited, aren’t you…?”
When I couldn’t answer, a smile of pleasure and triumph bloomed across Yuzuki’s face.
But at that exact moment, soft footsteps came from the kitchen. Luna emerged holding a glass of water.
In an instant, Yuzuki wiped all expression from her face as if nothing had happened.
The impish, devilish smile vanished. Her eyes sank into blank calmness. At the same time she withdrew the foot that had been tormenting me, straightened her legs, and returned to a perfect dining posture.
I quickly leaned forward as if nothing were amiss. Every trace beneath the table disappeared without a trace.
Luna sat down without the slightest suspicion.
“There was an ice tray in the freezer, but it was empty. I took a minute to fill it with water.”
Her carefree voice brushed past my ear and my heart stuttered one beat behind.
Luna had no idea what had just been happening under this table.
Yuzuki, looking perfectly composed, lifted a spoonful of rice as though nothing were wrong. Yet her gaze remained fixed on me, and it wasn’t satisfied.
I realized with a sinking feeling that this wasn’t over.
As if to confirm it, the tip of her foot continued to tap lightly against my leg—not pressing my groin outright, but clearly warning me not to relax.
Just when I thought my body was calming down, it began to stiffen again.
Then it happened.
With a soft clink, the glass of water beside Yuzuki tilted and toppled across the table.
I looked at her in surprise. Her expression wasn’t one of panic—it was strangely awkward, almost deliberately blank.
The spilled water spread slowly across the tabletop, then began dripping off the edge onto the floor.
A chill touched my bare feet. Only then did Luna rise from her chair.
“I didn’t think you made mistakes like this, Yuzuki. I’ll grab a dishcloth…”
Yuzuki raised her hand urgently.
“No, it’s fine. I’ll clean it up. Luna, just keep eating.”
“But…”
“It was my mistake, so I should fix it.”
Luna nodded and sat back down. Yuzuki pushed her chair back naturally, fetched a dishcloth from the kitchen, and crawled under the table to wipe up the water.
That was when I felt an unfamiliar, firm pressure against my groin.
Suspicion rising, I cautiously lowered my head.
My eyes met Yuzuki’s beneath the table.
With her long hair cascading down, she knelt there looking up at me.
The moment our gazes locked, Yuzuki slowly pushed the dishcloth aside. Her eyes lowered as her hand slid onto my thigh.
And then—
She began to pull down the zipper of my uniform pants.
The faint metallic whisper of each tooth separating sounded like a heartbeat against the quiet morning meal.