How Using My Oppai Skill to Enlarge My Sister’s Breasts Led to Building a Harem - Chapter 51.1: Special - MMA Girl

Chapter 51.1: Special – MMA Girl

On a summer break day, I’m sprawled on a makeshift ring in some venue, writhing in agony.

(Seriously, how’d it come to this…?)

Clutching my throbbing stomach, I curl up, rolling side to side. Above me looms a single woman.

“What, already napping?”

“Kuh—!”

Her middle finger jabs at me, and I force my aching legs to move, slamming them down to haul myself up.

(If that’s how it’s gonna be, I’m getting serious…)

Beneath my mask, my fighting spirit surges.

“Hah! Bring it, kid!”

Giving up now would crush my pride as a man. Worse, it’d betray those counting on me. So—

“Uooo!!”

“Tch!! Too soft!!”

I charge at my opponent, the female pro wrestler Shishidou Kokoro-san, with a tackle.

(It all started with a sudden call… from her—)

※

While studying at the Saionji annex—now my home—a message pings from the adult actress Hoshizora Rei-san. It’s not unusual; we hook up at hotels when schedules align.

But this time, something’s different.

“Please, I’m begging you!!”

“Uh… Why me?”

She bows low, rattling off her request in a rush. The details, though, are tricky—hardly something to agree to lightly.

“You’ve got an impressive build, and you’ve trained in martial arts, right?”

“Well, kinda… It’s not flashy or anything.”

What Miyabi-san teaches me is self-defense, not the spectacle Rei-san seems to expect.

“It’ll be fine. They’re the ones making outrageous demands.”

“Ha…”

“They” refers to the opponent pitched by her adult video company—

“Shishidou Kokoro-san, the pro wrestler, right?”

She’s the number-one beauty in pro wrestling, a star in her field.

From what I hear, she agreed to appear in an adult video but only if someone could beat her in a legit wrestling match.

“What a wild condition…”

“Our top actor’s a fan, so he jumped at it.”

“And got injured?”

“Yup.”

The actor, a real musclehead, overdid training, botched a fall, and hurt his neck.

“Not something amateurs should mess with.”

“I’m an amateur at wrestling too…”

My falls are drilled to perfection, so I’m unlikely to screw up, but pro wrestling? I barely know it.

“But you’re super strong, aren’t you? Riria-chan was bragging.”

“…Not that strong…”

I could handle amateurs, but my opponent’s a pro. And while she’s a woman, people like my mentor Miyabi-san prove women can be powerhouse fighters. It’s tough to respond.

“Please! I won’t get mad if you lose!”

Rei-san’s dead serious. Even in a post-lunch diner, a woman rubbing her forehead on the table isn’t a great look socially.

“Alright. Since it’s you asking, I’ll do it.”

“—Thank you! I knew you’d say yes!”

Her teary face flips to a radiant smile in seconds.

(That’s an actress for you…)

Rei-san’s a sexy star, but still an actress. Crocodile tears are probably second nature. I fell for it easily, but I don’t feel too bad.

“Beauty’s an advantage, huh…”

“Hm? Say something?”

“Nothing.”

I used to be her fan. Even now, as fuckbuddies, I can’t treat her carelessly.

“Win, and I’ll give you a reward. Give it your all♪”

“Ha, sure.”

And just like that, I’m set to star in a mainstream adult video.

※

On the promised day, I wait in the locker room, clad in black trunks, wrestling shoes, and a mask covering the upper half of my face.

(Looking like this, I kinda fit the wrestler vibe…)

My body, honed to its limits daily, ripples with rock-hard muscle. Scientific training and optimal diet have pushed me to my genetic peak.

185 cm—90 kilos.

That’s my current spec. My height’s still climbing, but more muscle would slow me down. Per the Saionji specialists, I’m at the perfect edge.

(Feeling… good.)

This morning’s sex session left me energized, my body taut. My pecs pop more than usual, my fat-free abs carved like a chocolate bar.

“Sorry, man, making you fill in for me…”

“No worries, injuries happen.”

The original actor, neck braced and looking rough, comes to greet me.

“I know it’s rich coming from me, but if it gets dicey, tap out, yeah?”

“Haha, thanks.”

He’s genuinely worried, his braced neck a stark warning.

“And if you win—”

“Straight to the main event, right?”

“Y-Yeah… You good for that?”

With extras and cameras rolling, it’s public sex. He’s wondering if I can perform under pressure.

“I’m fine. Sex is my specialty.”

“R-Really…”

It’s my one true talent. Filming or crowds don’t faze me—give me a beauty, and my cock’s ready.

(Shishidou Kokoro-san… She’s a looker…)

Among countless female wrestlers, she’s a charismatic beauty at 29. Brown-dyed hair, sharp features, a Yankee vibe. Fierce eyes and a wild streak in matches, but decent fan service, apparently.

“Win for sure! I’ve got a reward ready!”

“Yes, ma’am.”

Losing as an outsider would tank her rep. That means—

I gotta win.

With that resolve, I stride toward the gym’s 3,000-capacity ring.

(Pretty big crowd…)

It’s not real pro wrestling, but the front rows are packed with actual people.

I walk the aisle between them, slipping quietly into the ring.

Then, blaring metal music shakes the arena at ear-splitting volume.

Roaring cheers erupt.

With flashy entrance music, Shishidou-san appears, draped in a crimson robe.

“Shishidou!!”

“Kokoro-sama~~~!”

The crowd’s screams threaten to split the venue.

(Wait, are these real fans…?)

Stunned by the unexpected fervor, I freeze. Meanwhile, Shishidou-san saunters to the ring, spinning mid-air to land on the mat.

Another wave of cheers.

From that dazzling entrance, she grips her robe—

And flings it skyward.

Beneath, a golden bikini clads her sculpted body. Honed to perfection, not an ounce of fat—a warrior woman’s ultimate physical artistry.

True to her ring name, she stands like the king of beasts. Then, she grabs the mic, turning to me.

“So, you’re my opponent today, huh?”

“…”

“Just ‘cause you’re big, you think you can beat me?”

“…”

“Can’t talk, big guy? Guess I’ll make you squeal quick.”

Her rough words goad me.

I’m just a masked wrestler, a prop in this show. My role: stay silent, wrestle Shishidou-san, and win.

(Let’s see how this goes…)

Swallowing the urge to be overwhelmed, I take a deep breath under my mask—then the starting bell rings.

(First, just a light test—!?)

“Oraaa!!”

Before I know it, she’s in my face, her stunning features twisted ferociously, swinging her arm.

Bachin! A left slap cracks my face. A right kick slams my ribs, bending me, followed by a knee to my jaw.

Reeling, I back into the ropes, guarding up. Shishidou-san unleashes a brutal flurry.

(This wasn’t in the plan…!)

The script said we’d start slow, trading moves, then go with the flow. But—

“What’s wrong?! Ora ora ora!!”

I’m getting pummeled from the start. Palm strikes rattle my guard, mid-kicks stab my gut, and as I freeze, a vicious low kick hammers my thigh.

Even my maxed-out body screams under her relentless assault.

Arms crossed, I shrink, shielding my centerline. Her attacks rain down on my guard.

“Waaaa!!”

Deafening cheers. Each blow to my muscles, each sway of my body, draws wordless screams from the ring.

“Go down!!”

“—Ogo!?”

Anticipating a mid-kick, I miss her crescent kick slicing through my guard, her foot burying into my thick abs.

The impact drops me to my knees.

“Shaaaa!!”

Raising her fist, Shishidou-san struts, hyping the crowd. A muscled man crawling, a gorgeous fighter towering—the contrast whips the audience into a frenzy.

Ear-splitting cheers.

Harsh insults pelt me as I writhe, clutching my gut. She approaches slowly—

“You squeal nice, kid.”

Her taunting smirk and raised middle finger goad me further.

※

Back to the start.

“Then I’m going all out…”

“Hah! Come at me, kid!”

Recovering, I launch a tackle at Shishidou-san. It fails.

(Oh, right… She used to wrestle too, didn’t she?)

She counters from above, and despite our size gap, I’m slammed face-first into the mat. Without pause, she slips behind—my lapse lets her take my back instantly.

“Guh…! Oraaa!!”

“No way!?”

Nearly twice my weight, yet she hoists me from behind, hurling me with a backdrop, crashing me onto the mat.

My body arcs, slamming down with force. The graceful trajectory must look like art.

Another roar of cheers erupts.

(Gu… Straight on my back… Wait, huh?)

No pain.

Despite the thunderous impact, the damage is minimal.

“(Hey, you’ll lose by pin,)”

“Wha—oh!”

The count’s started. In pro wrestling, three seconds with both shoulders down means defeat. Her voice jolts me, and I twist free, the ref signaling 2.9 seconds—match continues.

(What… She tipped me off?)

If I’d stayed down, I’d have lost. Yet she noticed my daze and whispered a heads-up.

(And… nothing hurts…)

The earlier flurry, that throw—painful, sure, but not debilitating. She never punched with fists, only hitting my guard or thick muscle.

That throw, too. Flashy, but she dropped me clean on my back, letting my trained instincts take the fall.

(Could she… be a good person?)

“Still going, ora!!”

Just as I think it, a sharp slap flies.

“Guh…!”

The pain stings, but my earlier tension’s gone. I’m starting to get it.

Hurting without breaking, hyping the crowd—her artistry. Blending combat and performance—the essence of show business.

And pro wrestling—this sport’s thrill.