I pressed my mouth against Matsuri's.
The moment our lips touched, I felt her body stiffen, but she quickly relaxed.
My fear that she might reject me had been unfounded.
"Mmm..."
Matsuri let out a soft sigh.
Sensing a faintly sweet scent, I was tempted, and instinctively slipped my tongue into her mouth.
This time, I braced for her to pull away, but to my surprise, Matsuri accepted it as if it were natural. Tentatively, she began to entwine her tongue with mine.
"Haa... mu... chuu..."
The slow, wet sounds of our tongues intertwining reverberated directly into my mind.
The guilt of siblings doing something we shouldn't... finally began to surface.
Yet in stark contrast, an indescribable, intense arousal surged within me. Even I didn't understand why I was so aroused.
I knew I shouldn't, but instinct told me I absolutely didn't want to stop.
Like a beast that had lost its reason, I ravenously devoured Matsuri's tongue.
Our movements were still clumsy, but the pleasure of our mucous membranes touching melted my mind into a puddle.
For tens of seconds, or maybe minutes—I couldn't tell how much time had passed—I finally pulled away from Matsuri's lips.
Seeing my dazed expression, Matsuri chuckled softly.
"We did it..."
"U-um... yeah... but it's not like I could help it, Matsuri. You were making sounds. I had to cover your mouth..."
"Yeah, I guess you're right..."
Matsuri quickly agreed with my flimsy excuse.
As if absolved of guilt, I kissed her again, probing her mouth even more roughly than before.
"Haa...nn... haa, nchuu..."
But in reality, it was hardly effective at muffling the sound. These breathy moans still escaped.
Matsuri must have known this too. Yet she didn't resist, striving to respond to my tongue. We both understood, yet neither of us stopped kissing.
Realizing this, I suddenly felt a surge of excitement. As our tongues intertwined, I resumed moving my hand, which was pressed against her lower abdomen.
"Nmm... haa...nn... ah..."
Matsuri let out a deep, troubled sigh.
Even through the fabric, my fingers clearly felt the dampness between her legs.
Thirsting for more stimulation, I pressed down on her slickness, grinding my fingers up and down.
"Fah, ah... haa, chuu...nn..."
Matsuri's breathing quickened further.
To muffle the sounds, I pressed my lips together and thrust my tongue deep into my mouth.
With each thrust of my fingers, Matsuri's body jerked obediently. With each repetition, her reactions grew stronger and stronger.
Sensing that I might bite my tongue if I continued, I withdrew my fingers and pulled my mouth away.
"Haa... Haa... Haa..."
Matsuri panted heavily, her expression dazed.
Even to an amateur's eyes, it was clear she was highly aroused.
Staring at my younger sister's face, which I'd never seen like this before, I found myself transfixed. Then, without warning, Matsuri suddenly pushed her lips forward and made a soft, "Nn-."
Surprised, I instinctively responded, and her tongue shot out. I braced myself against the force, then countered by driving my fingers even harder.
"Ah, ah... mmm... chu, nnn... haa... mmm..."
As I continued to caress her with my tongue and fingers, Matsuri suddenly gripped my forearm tightly, as if pleading for something.
Seeing she wanted to speak, I pulled back slightly, separating our lips to hear her.
"What is it?"
"...Um, well... I think... I might be about to... you know..."
"What do you mean, 'about to'?"
"So, um..."
"Matsuri, you know the rules... You have to say it properly when you're about to come..."
I repeated Miki's mantra, though I was surprised she was already this close. It seemed almost too easy.
Well, considering how long and how much effort it took to warm her up, it was actually quite quick once she was heated.
But I didn't let up, unable to rest, keeping my hands moving continuously.
"S-such... Ah, haa, haa... Th-this is so embarrassing..."
"N-no, it's not embarrassing at all. Seeing Matsuri when she's feeling good... it's... it's cute."
The words left my lips, and my heart began pounding even harder.
This wasn't said with any ulterior motive; it came straight from the heart.
I want to see. I want to see Matsuri's face when she comes.
Come to think of it, last time—partly because I was so tense myself, but also because of our position—I couldn't see her face at all.
So this time...
I stopped kissing her and pulled back, focusing intently on Matsuri's expression while concentrating all my senses in my fingers.
"Show me how you look when you come."
"N-no, don't look! Ah, aah... It's so embarrassing!"
Matsuri protested and tried to turn her face away, so I forcibly held her still with one hand, forcing her to face me.
Then, I pressed my fingers against her most intimate area with firm pressure, making them vibrate rapidly as I aimed precisely for her clitoris.
"Ah! Ah! No, that's... Ah! I'm gonna... I'm gonna come...!"
With a shrill cry, Matsuri arched her back slightly and her entire body convulsed in spasms.
I stared intently, without blinking, at Matsuri's lightly closed eyes as her face twisted in pleasure.
Seeing my younger sister's face for the first time as she came, I felt a thrill of excitement that sent shivers down my spine, along with a strange sense of conquest. Then, in my arms, Matsuri slowly opened her eyes.
"I told you not to look...!"
"Ugh, I'm so embarrassed!" she said, covering her face with both hands.
Seeing that bashful gesture nearly made me crack a grin. I gently placed my hand on Matsuri's head.
"N-no, really, Matsuri, you were just... so... c-cute just now."
At my words, Matsuri flinched slightly, sat up, and stared straight into my eyes.
"...Really? Cute?" she pressed, as if she needed to be absolutely certain.
...She's really latching on to this. And her eyes are so intense...
"H-honestly, really, really cute!"
"Yay! I did it!"
Matsuri's face lit up with innocent delight as she threw her arms around my neck and hugged me tightly.
What's going on? Who is this? Is this really Matsuri? My younger sister? This is exactly what they mean when they say, "My younger sister is actually like this..."
Apparently, once you get my younger sister off, she turns all soft and clingy. What kind of condition is that? What kind of R18 heroine is this?
"Haaah, that felt so good... This is dangerous. I might get addicted..."
"Huh. So it was that good?"
"Mm-hmm, I love how good it feels..."
Matsuri's voice turned syrupy sweet, like a completely different person. Just like the last time she was all clingy. My guess seems to be right.
Clingy Matsuri is certainly cute, but... there's something faintly unsettling about it that makes me a little nervous.
Matsuri has a habit of drifting toward whatever's easiest or most fun. That's probably how she ended up becoming such a hopeless idiot, slacking off on her studies and wallowing in decadence.
Now that she's experienced something so pleasurable, she might awaken to some weird new addiction...
Matsuri clung to my body for a while, as if savoring the closeness, but suddenly pulled away.
Then, with a mischievous grin spreading across her face, she looked up at me.
"Hey, hey."
"...Hmm?"
"This... it's so swollen, you know?"
She pointed at my bulging crotch, which was practically bursting at the seams.
Naturally, my cock was already at its limit, probably flooding my underwear with a massive amount of pre-cum.
"You've been pressing against my back for ages. I know you felt it."
"Y-yeah..."
"Matsuri, did you do this to me? Huh?"
"N-no, ha ha ha..."
"Well, you can't help it, I guess. Then next time, I'll make you feel good, okay?"
Matsuri giggled, her smile meltingly sweet, and reached out to pull down my pants.
Something about this situation feels off... And having my younger sister try to undress me is embarrassing. Reflexively, I clutched my pants and resisted.
"Hey, wait a minute..."
"No! Just listen to Matsuri!"
"But I said no..."
"Why? Why won't you listen to Matsuri?"
Matsuri, who had been smiling moments before, suddenly looked like she was about to cry, her eyes glistening with tears as she turned to me.
Ugh, this feels...
A vaguely familiar scenario flashed through my mind, accompanied by unpleasant memories.
When we were little, Matsuri used to throw tantrums like this whenever things didn't go her way.
Her whining was so irritating that I'd reluctantly give in, but it never ended well. I usually ended up getting the short end of the stick.
But when she pulls this, I can't help but feel powerless to resist. It's like a conditioned response—she's somehow managed to tame me completely.
When was the last time I saw Matsuri pull her little tantrum? It was so long ago I can't even remember—years and years.
And now she's actually using it here...
"O-okay, okay, I'll do as you say..."
"Really? Yesss! Thank you, big brother!"
Matsuri's face lights up with an innocent smile, making my heart skip a beat. It's exactly like it used to be.
Matsuri really should thank her parents for giving her such good looks. This wouldn't work at all if she were ugly.
In the end, I give in and do as Matsuri says. To make it easier for her to pull down my pants, I stretch out my legs and lift my hips slightly, helping her.
Now all giddy, Matsuri braces herself against my erect cock as she smoothly pulls her sweatpants down to her knees.
As expected, her underwear appears, stained with a large patch of pre-cum.
Matsuri mercilessly yanked my pants down, finally revealing my rock-hard, pre-cum-covered penis to the world.
"Look at that! It's so big! A huge wee-wee!"
Matsuri said "wee-wee" without hesitation. Somehow, I felt like this was the first time.
She brought her face close to my penis, stared at it intently for a moment, then suddenly reached out and touched it with her fingers.
"Wow, it's so slippery!"
Matsuri pressed her index finger against the tip of the glans, which was just peeking out from under the foreskin, and began tracing small circles.
The fully aroused penis sent a brain-piercing pleasure through me with that simple touch alone.
"Hehe, does that feel good?" Matsuri asked, looking up at me while continuing to swirl her finger around the tip.
Before I could even answer, my penis jerked violently in response.
"Ah-ha! Your wee-wee's answering! You like it, don't you? You know this tip is your favorite spot, right?"
"S-such a thing, ha ha, wow, Matsuri... you're really something..."
"Right? And you're covering up the good part with that skin, aren't you? So, can I see it all?"
"U-um... yeah..."
Matsuri's aggressive advances left me feeling a bit overwhelmed.
Past experience had taught me that in situations like this, a few careless compliments usually smoothed things over.
It seemed that the affectionate Matsuri was surprisingly proactive when it came to intimacy.
Or maybe she'd always been intensely interested, and now her usual restraint had completely vanished.
Matsuri pinched the center of my glans with her fingers, then began pulling the skin downward.
After recent events, I'd realized I needed to practice peeling back my foreskin, and it was now coming off much more smoothly than before.
"Wow, a pink one! So naughty~"
Matsuri giggled excitedly as she slowly continued to pull the skin down.
I was paying close attention, but my head was already buzzing with excitement, and the slight pain was barely noticeable.
In fact, the friction of the skin against the glans felt good. Before long, the skin had fully retracted, completely exposing the glans.
"Wow, the tip is so plump... Such an erotic shape. Oh, it's getting slippery again..."
Matsuri quickly scooped up the pre-cum oozing from the glans with her finger, lifting it up to show the glistening strands.
Then, with earnest enthusiasm, as if playing with a toy she'd been given, she began smearing the fluid across the glans, her finger gliding over its surface. She seemed to be thoroughly enjoying the penis's twitchy reactions with each touch.
After playing with the glans for a while, Matsuri leaned in so close it felt like she was daring me to object, sniffing intently to catch the scent.
She traced her tongue from the base to the tip, then returned to the underside, where she began slithering her tongue along the ridge.
"Ah..."
"Hehe, you like this, don't you?" Matsuri chuckled smugly, her tongue flicking and sliding against the underside of my penis, tickling the sensitive underside.
The mere touch made my cock jerk and arch as if it had a mind of its own.
"No! Don't move!"
Quickly, Matsuri gripped the base of my penis, immobilizing it.
Then, as if licking a soft-serve ice cream, she began earnestly licking up the underside in earnest strokes.
"Ugh..."
The piercing pleasure made me gasp, and Matsuri seemed encouraged, varying her tongue's movements even more.
Starting from the underside, she licked around the sides, the glans, each area in turn.
Trapped in place, my penis was completely exposed to the direct stimulation of her tongue.
As the most sensitive parts were relentlessly teased, my hips began to twitch involuntarily.
"Wow, that feels so good... So, how about this?"
This time, Matsuri used her free hand to gently knead the sack.
Her fingertips caught hold of my balls and began lightly rolling them. It was... indescribably good, almost painful.
"What a strange sensation... Whoa, it's grown again? It's so hard..."
Matsuri continued stroking the sack while her tongue relentlessly teased the glans, now rock-hard and even more sensitive.
Her licks were meticulous yet uneven, somehow managing to tease me, whether intentionally or not.
The sensation was pure glans torture, so intense that my mind felt like it might unravel.
But this way, I felt like I was about to come, yet couldn't.
My mind had long surpassed its limits of endurance, consumed by the urge to ejaculate, making every moment feel excruciatingly slow.
If she would just give the shaft a little more attention, I'd come instantly...
Is Matsuri doing this on purpose? No, it's not Miki. She probably isn't even thinking about it.
After enduring the relentless glans torture for what felt like an eternity, I finally spoke up.
"Uh, hey..."
"What is it?"
"C-can you... put your mouth on it?"
"Put my mouth on it?"
"N-no, I mean, like Miki-chan did before..."
"Miki?!"
Matsuri's expression darkened visibly.
Apparently, the mere mention of Miki had suddenly put her off...
"Let me make this clear: I can do that too, no problem!"
With that forceful declaration, Matsuri wasted no time, taking the glans into her mouth with a firm pop.
The glans was enveloped in a warm, soft, and slick sensation.
"Mmm, mmm..."
Matsuri kept her mouth around it, moving her lips and tongue in a sloppy, wet motion.
It was a bizarre way to perform fellatio, but it didn't feel much different from the previous glans torture.
What the hell is she doing? Come to think of it, has she ever even sucked her boyfriend's penis before?
Comparing her to Miki feels wrong, but her technique is riddled with flaws. I guess I'll have to teach her properly.
"Uh, um, just... keep your mouth around it and try moving back and forth like this..."
Unable to stand it any longer, I gave the instruction. Matsuri obediently followed my words, moving her head back and forth.
Squelch, squelch. She took the shaft halfway into her mouth before pulling back.
It was excruciatingly slow, but the stimulation I'd been craving for so long nearly made my legs go weak.
"Ah... that feels so good..."
"Really? It feels good?"
"Yeah, you're really good at this."
I stroked her hair as I spoke.
The key to handling Matsuri is to shower her with praise.
I used to do it all the time, but lately there's been nothing to praise her for, and if I push it, she gets annoyingly clingy, so I stopped...
The effect seemed to kick in immediately. The movement of her mouth on my shaft became deeper and faster.
Squelch, squelch...
Gradually, the base of my cock grew slick, glistening wetly.
Whether intentional or not, Matsuri's mouth was awash in saliva.
Every time her strokes returned to the tip, lewd schur sounds echoed around us.
Schurur... schpa, schpa...
Matsuri had watched Miki's fellatio earlier, so she might be imitating it.
Watching her, I got that impression, but compared to Miki, her saliva was much thicker and stickier, and the sounds were far more erotic.
In terms of pure technique for getting me off, Miki was still superior. But Matsuri's efforts were clearly earnest, her devotion to service radiating strongly.
Watching Matsuri diligently take my penis into her mouth and pull back, repeating the motion just a few times, I quickly reached my limit.
"Ah, Matsuri, I can't...!"
"Mmm?"
Before I could even warn her, an irresistible wave of orgasm crashed over me.
Misunderstanding, Matsuri instinctively took my penis deeper into her mouth.
By the time I thought, Oh no, the thick stream of semen had already erupted violently into her mouth.
Dok, dok, dok...
"Mmm?! Mmm, mmmuuh..."
Matsuri let out muffled groans, but unable to resist the allure of climax, I thrust my hips upward, pushing my entire penis further into her mouth.
With each violent spasm of my penis, waves of intense pleasure coursed through me.
Throughout, I subtly thrust my hips forward, ensuring every last drop of semen was expelled into Matsuri's mouth.