"Haa... haa... ngh... haa, ah... nuu, haa..."
For several minutes, Miki relentlessly fondled Matsuri's breasts.
The ticklishness lasted only a few seconds at the beginning.
After movements that were no longer even remotely plausible as camouflage, Miki's hands immediately moved to Matsuri's chest, tormenting her.
"...Ngh... haa, haa... ah, ah... haa, haa..."
Matsuri's breathing grew labored, yet she desperately tried to suppress her moans.
At first, she had insisted it only felt ticklish and that she wasn't aroused, but she had long since lost the strength to make such claims.
No matter what she said, her ragged breathing and flushed face made her state obvious to anyone watching.
Eventually, Miki's fingers, which had been kneading Matsuri's sensitive areas through her clothes, paused for a moment.
"Haa... haa... haa..."
"Wow, that's incredible! I can't believe you're holding on. You're just too good, Matsuri-chan."
"Haa... Nngh? O-oh, it's... over...?"
"Nope, still about two minutes to go."
Matsuri's eyes were unfocused and glazed over, her words barely coherent. She wasn't just enduring this—she was completely defeated. Her sense of time had completely warped.
The original five-minute rule had long been forgotten. It had probably been far more than five minutes by then.
To be honest, neither of us had been keeping strict time from the start.
Both Matsuri and I had underestimated Miki's methods, her techniques.
I never imagined this situation would arise in just a few minutes.
I'd even forgotten to secretly rub my penis against her, too absorbed in watching Miki's movements. But when her hands stopped, I suddenly snapped back to reality.
I met the eyes of Miki, who was beaming with delight.
With a mischievous grin, she suddenly reached out and took my arm.
Matsuri's body had already gone completely limp, making it unnecessary for me to hold her in a rear nelson.
To be more accurate, I was simply sitting cross-legged behind her, supporting her upper body.
With one arm cradling Matsuri's flushed body, I let Miki pull my other arm forward.
Her hand guided my fingertips to Matsuri's chest, coaxing them toward her sensitive nipple.
My heart began pounding fiercely.
My fingers finally touched Matsuri's breast. Even through her clothes, the erect nipple was clearly discernible, standing erect.
Matsuri, the main character, remained completely oblivious, her breathing ragged and unsteady.
"Ugh..."
Matsuri gave a small reaction even to the lightest touch.
Her soft, warm body, her panting breaths, and her stifled moans.
All of it instantly stoked my arousal, stripping away my normal capacity for rational thought.
Before I knew it, I was driven by the impulse to stimulate my younger sister's body further, to make her pant even more.
As if she could read my mind, Miki silently urged me on with a wordless "Go on."
You've been watching this whole time, haven't you? she seemed to say. Now try it yourself.
I'd never touched a girl's breasts before and had no idea how to do it, but now I was certain I could manage without a problem.
After all, the visceral experience of reality was completely different from watching AVs on a screen.
My strokes were probably much gentler than what I usually saw in AVs. But either Matsuri was incredibly sensitive, or those AVs went way overboard.
Regardless, as if absolved of all sins, I tightened my grip on Matsuri's finger.
First, I gently tapped my finger up and down, rolling it over the hardened nipple through her clothes.
"Haa, haa, ah..."
Matsuri's body jerked in my arms. This was definitely working.
Even though she was already climaxing, the fact that Matsuri was feeling pleasure from my touch alone excited me even more.
Her voice, husky and unfamiliar, made me want to hear more of it.
I gradually increased the pressure of my finger.
"...Haa, haa... Nnn, nuu..."
"Wow, big bro, you've got amazing muscles!"
"...Huh? What...? ...Huh...?"
Matsuri gave a slight reaction to Miki's words.
Apparently, she'd noticed my hand touching her.
"U-um, wh-what are you...?"
Matsuri twisted her body slightly, but her resistance was feeble, as if she lacked the strength to fight back.
Now that she'd noticed, there was no turning back.
So, I shifted my position to embrace her from behind, reaching around from under her arms to grasp each nipple between my fingers.
Following Miki's example, I pressed the tips of my fingers against the nipples and began circling them in a stimulating motion.
"...Ah, ah... Stop that..."
"Hmm? What's wrong, Matsuri-chan? Does it feel good when your big brother plays with your breasts?"
"N-no... It just feels weird..."
Matsuri's body trembled even more violently.
With our bodies pressed even closer than before, her reactions hit me directly.
Feeling clear resistance, I continued moving my fingers relentlessly.
"Hah, hah, ah... n, ah..."
"Matsuri-chan, you're making such funny noises. But just as I expected, you've been watching my weak spots, big brother."
"Huff... huff... ah... nnn, no, no, I can't... I can't anymore..."
"Hmm? Already done? Giving up? Hmm... I think that's enough for now. Big brother, stop for a moment."
I felt like we were just getting started, but the order to stop came.
I wanted to push her to her absolute limit, but obediently withdrew my hands from Matsuri as instructed.
After all, I had a strong premonition that Miki, that schemer, would never let something end so half-heartedly.
"Huff... huff... Is... it over...?"
"Yeah, it's over, but... What's wrong, Matsuri-chan? Why are you squirming like that?"
Whether she was aware of it or not, Matsuri was restlessly rubbing her thighs together.
Noticing this, Miki pointed it out sharply, causing Matsuri to abruptly freeze, startled.
"...I just... feel... itchy... down there..."
"Hmm? Where exactly?"
"B-below..."
Matsuri answered Miki's questions in a dazed, almost hypnotized state, her breathing shallow and ragged, her body limp and her words slurred.
Her gaze drifted aimlessly, as if she were in a trance.
"Mm-hmm, I see... So Matsuri-chan's little pussy is getting all itchy now, isn't it~?"
"N-no, that's not it..."
"Hmm? What's different about it? You want your clitoris stimulated too, don't you?"
Miki's suggestive words made Matsuri weakly shake her head back and forth.
"Why not? C'mon, your brother said he wants to watch you do it, right? You've seen him working hard down there, haven't you? So you should show him too. That way we're even, right?"
Of course, I never said anything like that, and it was a pretty forceful argument. But apparently, Matsuri's rational thinking had completely gone out the window, and Miki's words were enough for her.
Matsuri didn't exactly agree, but she stopped resisting.
Taking that as tacit consent, Miki rolled up Matsuri's skirt, forced her legs apart, and Matsuri simply let her.
Matsuri's limp hand was taken by Miki and guided between her spread legs.
"Go on, move it around. Find the spot that feels good and rub it."
"...Ugh, it's so embarrassing..."
But she didn't move it herself. Perhaps she simply lacked the energy to resist.
"See? You can do it. Just like you do it yourself, right?"
"How would I know that? I've never done it before..."
"Huh? Matsuri-chan, you've never done it alone?"
"No way! It's scary..." Matsuri answered Miki's question with childlike honesty.
Surprisingly, it seemed she really hadn't masturbated before.
After a moment's thought, Miki decided not to force it and released Matsuri's hand.
"Right, let's get my brother to help us."
Miki switched tactics, pulling my hand and guiding it to the crotch of Matsuri's pants.
From where I stood, I couldn't see clearly, but the moment my fingers brushed against her, I could tell her panties were soaked.
Along with that, they were surprisingly warm.
"N-no, wait..."
"But Matsuri-chan, you did it with your hand before, so now it's your turn to let someone else do it."
Matsuri protested half-heartedly, but Miki's mysterious logic quickly subdued her.
Pleased with herself, Miki began moving my fingers up and down against Matsuri's crotch.
My fingers swiped across the unnaturally damp fabric, which clung to moisture like a sponge.
At first, Miki's hand moved slowly in circular motions, as if probing Matsuri's reactions, systematically exploring every inch.
After a while, Miki suddenly stopped moving her hand. Then, without warning, she pressed my fingertips against Matsuri, pushing them in with a soft, yielding force.
"Ah!"
Matsuri gasped, her voice trembling.
Miki subtly adjusted her position and thrust her fingers in again, twice, then three times in quick succession.
"Aun..."
On the fourth thrust, Matsuri let out a louder cry, her body jerking violently.
Without mercy, Miki pressed down harder, probing the same sensitive spot with my fingers.
"Nn... Nnn!"
Matsuri's voice grew increasingly shrill with each thrust.
It seemed Miki had already pinpointed Matsuri's most sensitive spot.
After repeating this rhythm of thrusts for a while, Miki's hand suddenly released my fingers.
"Huh?" I instinctively paused, but Miki shot me a meaningful look.
Understanding her intention immediately, I tightened my grip and resumed the same movements as before.
"Aah, ah, ahh!"
Matsuri's reactions intensified even more.
It wasn't so much helping her anymore; I was now completely in control, manipulating her intimate area.
Alone, I wouldn't have known what to do or where to focus, but thanks to Miki's guidance, I was quickly grasping the technique.
My hands were making her tremble and climax like this. An indescribable sense of conquest welled up inside me.
This feels so good... here...
As I gained a bit of composure, my fingers explored, and I felt a slightly swollen, raised bump.
This is Matsuri's clitoris... Even through her underwear, it's swollen so prominently. How lewd.
I swallowed hard. My penis, pressed against Matsuri's body, was so hard it hurt.
As I teased her clitoris with my fingers, I unconsciously rubbed my painfully erect penis against the back of Matsuri's shirt, which had ridden up.
Pre-cum flowed profusely, slicking our skin and making the glans glide smoothly, wetly against her.
As I frantically ground against her, the foreskin began to roll back slightly, exposing the glans to direct friction and intensifying the pleasure.
The more I moved my hand, the more Matsuri's body arched, and the more vigorously the glans rubbed against her.
Having tasted this pleasure, I kept my fingers exactly where Miki had taught me to touch her, stroking them faster and harder.
"Ah... ah... ah... aah..."
Then, something shifted within Matsuri.
Her voice suddenly changed. She wrapped her arm tightly around my wrist, clinging to me.
"What's wrong, Matsuri-chan?"
"...Ah, ah! No, ngh... S-something's... ngh!"
"Are you going to come? Matsuri-chan, are you going to come from your big brother playing with your pussy?"
"S-stop, stop! Ah, ah... No, no!"
At that moment, Matsuri's body jerked violently, even more violently than before.
Then she began convulsing repeatedly: thud, thud, thud.
Did she actually come? Matsuri, from my hand...? It was surprisingly easy.
Still, I had made a woman climax by touching her clitoris myself. A sense of accomplishment slowly began to sink in.
But there was no time to bask in that feeling.
Matsuri's spasming body roughly rubbed against my penis, and at the same time, I reached climax with embarrassing ease.
As her back arched and convulsed, I forcefully sprayed thick white fluid toward her.