How Using My Oppai Skill to Enlarge My Sister’s Breasts Led to Building a Harem - Chapter 50

Chapter 50

I was ambushed by Miyabi-san, and through sheer sexual prowess, I barely managed to fend her off, escaping the fate of becoming her puppet.

So, what happened next?

“Come on, little brother, open wide♪”

“Geez, Miyabi-san…”

“Hey, it’s Miyabi-oneechan, right?”

“Ugh, fine… Miyabi-oneechan.”

Miyabi-neesan had become utterly doting.

“Now, Miyabi, you can’t monopolize my darling.”

“Ayaka-sama… But as his sister, I cannot obey that command.”

“Muu… To think Miyabi would defy me…”

Caught between master and servant, I ate my meal.

“Here, darling, let me feed you. Say ahh♪”

To my left, my fiancée, Ayaka-san, who’s already borne my child.

“Ayaka-sama, that’s my duty as sister and maid. Come, ahh♪”

To my right, Miyabi-neesan, my step-sister and maid.

Both are breathtaking beauties, impossible to rank.

(Hmm, two flowers in hand, but… will they fight?)

I’d hate to see these two clash. As I fretted—

“Hehe, this reminds me of old times,” Ayaka-san said.

“Ayaka-san?”

“When we were little, Miyabi used to be quite rebellious.”

“Wow, that’s surprising.”

“Ayaka-sama, that was childhood.”

I’d heard Miyabi-san worked for the Saionji since she was young. Lonely back then, she was approached by Ayaka-san, and they became friends.

“So, you two are best friends?”

“Yes, exactly.”

“Calling myself Ayaka-sama’s friend is far too presumptuous…”

“Does Miyabi dislike it?”

“No, it’s not that…”

Despite her flustered pose, Miyabi-neesan’s joy was obvious.

(To me, it just looks like two gorgeous women flirting.)

Watching their warm bond, I mused. I’m an Amakawa now, but discussing adoption with my birth family caused quite a stir—

※

“Adoption!? Without consulting us… Dear, say something!”

“Hmm… But if he’s had a child with a Saionji heiress…”

“He’s our son! And what about Ai!?”

Ai—I’ll settle things with her properly.

Otou-san seemed resigned, aware of Saionji’s power. But Okaa-san wasn’t ready to let me go.

My resolve didn’t waver.

“Even if my name changes, I’m still your son, connected by blood. And—”

Back then, I was powerless. I might’ve failed to protect someone precious.

“I want to be great. To do what’s right, I can’t stay weak.”

That’s my honest truth. Meeting my parents’ eyes, I showed unwavering determination. I don’t know how it landed, but Okaa-san sighed softly.

“Fine. But come home sometimes. This is where you were born.”

“I’ll back you, son. The world’s unfair, especially to the powerless. If a man decides, aim to be the best.”

“Thanks.”

※

After that, I moved into the Saionji estate. Late July, with summer break nearing, I was pampered by maids, juggling studies, training, and sex—a whirlwind of activity.

(Is this heaven?)

Besides Ayaka-san and Miyabi-neesan, I’ve been intimate with ten other maids. To be blunt, I’ve been going at it nonstop.

It’s not my fault. My stamina’s practically infinite now—how could I not get hard for cute maids?

“Wow, darling♡”

“Goodness, little brother♡”

Lost in thought, my groin strained my pants, practically bursting.

The master and servant, mid-flirt, zeroed in on my bulge like predators.

I’d love to go all the way, but with Ayaka-san postpartum, pairing only with Miyabi-neesan would be unfair.

“Uh, maybe you two could… take care of me?”

“Yes♡”

And so, in broad daylight, I led two beauties to bed.

※

“How’s this, darling? My oppai♡”

“Mine too… They pale compared to Ayaka-sama’s, but—here♡”

Munyu, munyun♡

Two stunning, busty women giving me a double paizuri. The impact—

“Ugh… I leaked a bit.”

A little precum escaped just from their grip.

Seeing it, they lapped at my glans and shaft.

“Ufufu, rero♡ Delicious, darling♡”

“Oh, Ayaka-sama… Me too, chu♡ Rero, rerureruru♡”

“Chu♡ Such a splendid penis…♡”

“Chu♡ Its color, shape, size… Nothing could surpass it♡”

My cock became their toy, licked and sucked relentlessly.

“I’ll take the tip♡ Nn♡ Jyu♡ Jyupo, jyujyu, jyuu~~~♡”

“Then I’ll handle the shaft’s underside♡ Rero, nhaa…♡ Nrerorero♡ Chuu~~~♡”

(Like a dream… If this is happiness, maybe Miyabi-neesan’s paradise wasn’t so bad… Haha.)

My hazy mind half-joked as my limit neared.

“Ah… Aa… I’m cumming. Gonna cum!”

“Nn♡ Nn♡ Nn♡ Let it out, darling…♡”

“Jyu♡ Rerorero, jyuzuzu♡ It’s twitching, little brother♡”

Their ferocious double blowjob overwhelmed my glans and shaft.

Ayaka-san, face flushed, devoured my tip, jubujubu♡. Miyabi-neesan, unable to restrain her lust, huffed as she lapped my shaft.

Unable to endure, I climaxed pathetically.

Byururu…♡ Byuku♡ Byuku♡ Byuku♡

“Nfo♡ Nnn… Ngu♡ Ngu♡ Can’t swallow it all…♡”

“Oh, Ayaka-sama… Such a waste…♡ Rero, jyupa… Jururu♡”

The beauties vied to drink my semen. Floating in bliss, I gazed at the scene, drunk on pleasure.

(Paradise, huh…)

“Nn♡ Haa… I’ll take the tip now, little brother♡ Jurururu…♡”

“Ah… Aaaa!! Miyabi-oneechan…!”

“Nfufufufu♡ Jyubo♡ Jyubo♡ Jyubo♡ Jyuu~~~♡”

Caught off guard, round two began.

“Geez, Miyabi… Fine then♪ Rero♡ Rerureruru…♡”

They switched roles, intent on sucking me dry.

(Feels amazing… but how long will this go on?)

In the end, they kept at my cock until they were satisfied.

※

On a holiday just before summer break, I passed through my birth home’s entrance, waiting in the familiar living room for someone special.

“Otou-san and Okaa-san are as busy as ever, huh.”

I pictured her, unseen for half a year.

(Six months since we last met… Is she doing okay?)

Late February, hounded by media, I fled overseas—all Miyabi-neesan’s doing, a terrifying thought.

As I mused, the front door’s key turned, light footsteps approaching. She paused before the living room, then opened the door with resolve.

My heart stopped.

Standing there wasn’t just a person—an angel.

“Onii…sama.”

“Ai…?”

After six months, Ai’s skin was porcelain, her hair cascading to her back. Retaining traces of her middle school self, she’d blossomed into a stunning woman.

(What’s this pounding in my chest…?)

“It’s been a while, Onii-sama. Have you been well?”

“Uh, yeah… You look healthy too, Ai.”

What’s this unease? Who am I even talking to?

“I’ve adjusted to the academy, striving daily.”

“Good… That’s great…”

This beauty is my sister, no doubt. But why this distance?

“Hey, Ai… Can you drop that way of talking?”

“…Why would you say that?”

Her face clouded, eyes brimming with sorrow.

“It’s weird, isn’t it? Between us, talking like—”

“You like refined, elegant women, don’t you, Onii-sama?”

True, I adore graceful women like Ayaka-san or Miyabi-san—their poise is unmatched. But that’s not what I want from her—not this forced facade.

“Ai, you’ve always been captivating. You don’t need to change like this—”

“Liar…!”

Before I could finish, her sharp rejection sliced through our bond.

“We’re not siblings anymore, are we!?”

※

<Ai’s Perspective>

Today, Onii called me to meet at our family home.

It’s about what Okaa-san told me—his adoption.

Betrayal—that’s what I first felt. But maybe I jumped to conclusions. My kind Onii wouldn’t do that. I forced myself to act cheerful.

Yet—

“You chose Ayaka-san over me, didn’t you, you traitor!!”

“No, Ai, that’s not… I love you—”

“I don’t care!!”

Overwhelmed by grief and rage, I tried to flee the room. But—

“Wait!”

“Kyaa!”

His massive frame enveloped me from behind.

“Let go! I’m nothing to you now—not family, not anything! You don’t care about a girl like me, do you!?”

“You’re everything!! I—”

Struggling frantically, I thrashed against his hold.

(Why won’t he let me go…? He rejected me, didn’t he…?)

“I want to marry you, Ai!!”

(…?)

My mind blanked.

His words stunned me, body and mind rigid.

“What are you saying…? That’s impossible…”

We’re blood siblings. Even with adoption, that doesn’t change.

“It’s possible. Not here, but—”

“Not here…?”

“There’s a country where we can marry.”

“…What’s that? Live there?”

I didn’t understand. I’d never heard of such a place.

“No, I’ve got a special status there, so we’d be citizens without living there.”

“What…? I don’t get it…”

I’m ignorant, just a student, unlike Onii, who knows the elite world. Hesitantly, I met his eyes—sincere, unwavering.

“We can marry, Ai.”

“Really…? You and me, Onii…?”

“Yeah. We can be together.”

Together. Forever, with my beloved Onii…

I studied him anew.

(He’s… so handsome…)

No man could compare.

His chiseled, lean body—proof of relentless effort, far surpassing mine.

“Ai.”

My brother, with me since birth, now the world’s finest man—my prince. My heart raced.

His eyes drew me in, the world narrowing to just him. His lips parted for his next words.

“Marry me.”

A childhood memory flickered.

“Ai… You’re cute, huh?”

“Huh?”

“When we grow up, I’ll make you my bride!”

Innocent playtime, yet that moment lingered.

He’s loved me since then.

Realizing it, my doubts vanished instantly.

“Onii, I’m… so happy…”

I don’t know foreign laws. But I know when he’s telling the truth.

Because—

“I’ll marry you, Onii!”

We’re siblings.

※

“Onii, I love you so much♡”

“Ai… You’re gorgeous…”

We stripped, baring ourselves after so long. Fittingly, it was the anniversary of our first time, a year ago today.

Kuchu♡ Kuchu♡ Kuchu♡ Kuchu♡

“Your body’s too sexy, Onii♡”

“You too, Ai.”

Unable to wait, Ai fingered her pussy.

“Nnu♡ I’ve been holding back for six months…♡”

“Jerking off in the dorm?”

“Naa♡ Yeah… Thinking of you, playing with my pussy…♡”

“So naughty, Ai…”

Dripping honey, she teased her Onii-exclusive hole, kuchukuchu♡.

“Hate naughty girls?”

“Nah, I love them. The naughtier, the cuter.”

“Nn♡ Nn♡ Onii… Onii♡”

Her pussy melted, pooling on the sofa, its sweet scent invading my nose, stoking my male desire. Blood rushed to my groin, my glans swelling, shaft arching upright.

“I can’t hold back anymore, Ai!”

“Come on♡”

“Uoo…!!”

Zu, nyuuu♡

“Nnn~~~♡”

Her sisterly pussy sent shivers of ecstasy through me. Soft folds grazed my glans, clinging to my shaft.

“Gu…! We’re perfect together…!”

“Nhaa♡ ‘Cause we’re siblings…♡”

“Aa… Your pussy’s so soft! My cock can’t get enough…!”

Maybe it’s our shared blood, but our bodies fit flawlessly. No other woman matches this perfect grip.

(Her face, her body—leagues beyond before… This is…)

Ai was always a stunning beauty. But this half-year, her effort polished her white skin, glossy hair, and meticulous care honed her allure.

(Not just a once-in-a-millennium beauty… Once in ten thousand, no, a billion years!)

My heart throbbed achingly.

This was love.

“Gorgeous… I’m falling for you all over again.”

“Nha♡ What’s that, Onii♡”

Guchu♡ Guchu♡ Guchu♡

Stirring her pussy with my cock, I marveled at her beauty. Right now, I’d swear she’s the world’s cutest girl—by a mile.

“I just realized you’re the ultimate girl, Ai.”

“Haha, weird♪ An♡”

No joke. I’m a woman-obsessed perv, but Ai’s in a league of her own. I have to make her mine.

“Here goes… You’re mine, Ai.”

“Haa♡ Onii, Onii…♡ Aaa♡”

Paan!! — Paan♡ Paan♡ Paan♡ Paan♡

“So good~~~♡ Your cock’s too strong…♡”

“Just getting started!! Here, here… Here!!”

Channeling vital energy into my cock, I poured it into her. My power, now perfectly controlled, surged through her pleasure nerves.

“Nghii♡ What’s this… Amazing…♡”

“Feel good, Ai?!”

“So good~~~♡ Onii, it’s too much~~~♡”

Her pussy clamped kyuu♡, seducing my cock.

Zuchu♡ Zuchu♡ Zuchu♡

Her tight grip sparked intense friction, electrifying my hips.

(This kind of sex exists!?)

I’ve bedded many women, but this spine-melting pleasure was a first.

“Onii♡ Onii♡ My pussy’s tingling~~~♡”

“My cock’s buzzing… I’m losing it!!”

Our vital energy swirled between us, perfectly synced as kin. Pleasure signals flooded from head to toe.

“Oooo~~~♡ Onii♡ I’m… I’m cumming!!”

“Aa…! Me too! Oaa… Aa!!”

An unprecedented climax surged, awakening primal instincts.

“Get pregnant, Ai!! Bear my child!!”

“Nghiii♡ Can I? Have your baby?♡”

“Yeah…! I’ll take full responsibility!!”

Society’s judgments, norms—none mattered. Loving and creating life with my beloved was true love, I realized.

Dochu♡ Dochu♡ Dochu♡ Dochu♡ — Dochun!!

“A… A, cumming~~~♡”

“Nuu, aa~~~♡♡♡”

As Ai climaxed, my balls unleashed a torrent of concentrated semen.

Dobyuu♡

“Auu♡ Haa… So deep…♡”

“Pregnant! Reach your eggs, Ai!!—Guooo!”

With all my love, I sprayed my finest seed toward her eggs.

Exactly one year ago, at this moment, I lost my virginity—and impregnated Ai.

This ejaculation, my life’s greatest, was extraordinary.

“Onii…♡ It’s done… Our baby…♡”

“Yeah, I feel it… It’s conceiving… My strongest sperm…”

“Haha… My dream came true…♡”

Our bodies became erogenous zones, climaxing endlessly. Amidst the ecstasy, my mind was strangely clear.

“Ai… You’re my number one girl.”

“I know… You love me, Onii…♡”

“You love me too. I feel it.”

We’re one now. Her thoughts flow into me.

“I’ve always loved you…♡”

“I’ve loved you forever.”

My first love was my sister.

Now, it’s fulfilled.

“We’ll be husband and wife.”

“The best husband♡”

“The best wife.”

“Hehe.”

“Haha.”

Thus, we vowed to be together forever.

And—

“Ai, I’m gonna make you mine completely!!”

“Do it♡ Make me think only of you~~~♡”

“Alright, here!!!”

Zubon♡♡♡

“Oooo~~~♡♡♡”

Like that summer day, we fucked and fucked, pouring a year’s worth of matured love into each other, our bodies and hearts melting together.