“It’s… too deep. Slowly, please. Slowly.”

“Not yet.”

Thwack!

“Hngh!”

“Time’s… not up.”

Thud! Like cutting off a staccato, he thrust his hips upward the moment he spat out each word.

He was always gentle, yet cruel when counting. His hips slammed down hard, maintaining high intensity—treating s*x like an extension of exercise—moving just as sickeningly as back then.

“Aaaahhhh!!”

Instead, he increased the speed even more. A cruel tremor pierced through me from my entrance to the top of my head, making me feel like my entire body would be torn to shreds by the org*sm at this rate.

“Hnngh…”

Tears welled up, blurring everything into a hazy mess. The overwhelming pain from repeated friction faded, and instead, pleasure sparked with each blink of my eyes.

Smack! He suddenly pulled out his thick tip and slapped my as$.

“Turn over.”

When I couldn’t move quickly with my exhausted body, he grabbed my arm and flipped me over with ease. Then he threw the cushion to the floor and folded my legs up, making me hold them. 

He spread open my reddened entrance with his fingers. The swollen flesh stung at his touch.

“Seems like you need more p*ssy juice flowing?”

“Ahh…”

“What should I use? Fingers? Mouth? Or a toy?”

“Fingers, I like fingers.”

He immediately thrust two fingers inside.

“Aaah… ngh.”

The legs I was holding trembled and quivered.

His hands, which always corrected my form, constantly sparked s*xual fantasies in me, so I gladly chose fingers. More flexible than a p*nis, his long, bony fingers moved in and out of my entrance, roughly stirring my inner walls.

He bent his fingers to scrape the top, then changed direction to scrape the bottom. He spread the opening and inserted another finger. It became tight, so I tried lifting my hips, but he just persistently twisted them.

“Aahhng. I’m… I’m going crazy. Aaah…”

“I think you need more customized training. You do.”

He shook the fingers he’d shoved inside. My vaginal walls trembled and convulsed entirely with squelching sounds.

“For example, the know-how of not letting go of a c*ck, or how to swallow with your hole. There are muscles here too. You need to use them, client.”

“Hngh. Yes… I’ll do it. Haah…”

He pressed his fingertips against one spot and began rubbing it intensely. I immediately felt the anxiety of needing to pee. I hurriedly spread my legs and looked down, and the instructor pulled my hand over and placed it on my cl*toris.

“Rest time is over. You need to move again.”

Interval s*x was apparently still in effect. The spot he rubbed itched and drove me crazy, so without even being conscious of him watching, I started rubbing my cl*toris rapidly.

“Looks good. Spread your legs more.”

“Hnnngh.”

“You need to spread your hole too. You learned how.”

I tensed my lower abdomen like pushing something out. My entrance spread wider and he pushed his hand deeper. It seemed like everything except his thumb had entered. 

With not just his fingertips but his entire palm inside, it really felt like I was tearing, yet a strange pleasure melted my brain.

“Hngh. In… Instructor. It’s weird! It’s weird! Mmm.”

“Keep m*sturbating. You feel too much from your G-sp*t, so before we proceed with high intensity, I’ll raise the level here.”

“Hnngh. Ahh!!”

Rotating the palm embedded in my entrance side to side to widen the space, he then pressed his fingertips somewhere again and rubbed rapidly. My body didn’t feel like my own, so I let out shrill screams.

“Aaaaaah! Stop, stop! Plea… se. Hngh. I don’t know—aaah!!”

Splash. Water burst out. He pulled out his fingers and quickly rubbed above my cl*toris, making water spray everywhere. I trembled convulsively, unable to calm down below, just swallowing tears desperately.

But without giving me time to calm down, he positioned himself between my thighs again. 

Even while he found a comfortable position, my lower abdomen kept trembling endlessly and wouldn’t settle, making him suddenly feel overwhelming as he mounted me.

“Wait, wait a moment. Hngh…”

“I’ll increase the pace. If it’s too hard, you can just cry.”

He gripped his shaft and rubbed the tip against the drenched spot.

“I’ve kept your core solid all this time, so you’ll be able to endure. Let’s do what we can.”

No, stop talking like it’s training! Hngh.

He slapped the outside of my thigh with a smacking sound and pushed away my knees that tried to close.

“You need to spread them, client. You’ve been wanting to hold my c*ck all along. Then you need to spread wide and take as much as possible.”

“Ngh…”

Thwack! He rammed in like a bulldozer. I couldn’t twist my lower half held tight, so I thrashed my entire body. My back arched the opposite way and my head tilted back.

Thrust! Thrust! Raising the speed in one breath, he watched my risen br*asts bounce and pinched my n*pple hard.

“Aaahngh! Hahng…”

With one n*pple pinched hard, the instructor intensified his hip thrusts. The shaft penetrating me didn’t just stay in my v*gina—it felt like it pierced straight to my heart. 

He lifted his knees and stood on his toes, truly balancing his body’s center with just his arm strength and toes, then pounded his member in and pulled it out with squelching sounds.

Who knew the push-up position could be such an obscene motion.

Thud! Thud! Splitting the narrow passage, making squishy sounds as he buried himself to the hilt, breath burst from deep in my throat.

“Haah, seems like we have high f*cking compatibility too, client.”

“Hngh! Ins… Instructor.”

“You just need to build up your stamina a bit more.”

“Ah, ah, ah…”

Moans burst out in sync with the rhythm of each thrust. With the force pressing down so hard my lungs felt like they’d pop out through my throat, just being shaken filled my entire body.

“I have a pretty… haah… long pace.”

“Ah. Ah!! Mmm!!”

“Since it’s your first time today, haah… I’ll stop at a level that’s not too much.”

It’s been way past too much for a while now! If I want to keep up with him trying to fill his exercise quota with s*x, I might need to become a professional athlete.

“Aah. I think… I’m going to come. Instructor…”

“Yes. I’ll send you off.”

Unlike his polite tone, his hip thrusts became rough like the climax of today’s workout.

Thrust!

Thrust!

Driving down vertically, I flapped my body like truly skewered prey.

“Angh, nnnngh, mmm!!”

Momentarily, I couldn’t hold back a shrill scream. The ecstasy he made me taste was a dizzying, spicy flavor like my whole body was tearing and my muscles were pulled taut.

After screaming and swallowing my breath while enduring the tremors, he forcibly pulled out his thick gl*ns from the tightly contracting entrance, yanking out his ferocious p*nis like pulling a radish with a squelch! Then he immediately pulled my head while lifting his lower body.

“Kgh… ugh!”

His p*nis, shooting out s*men, was placed entirely in my mouth. The shaft thrust straight to the back of my throat, creating strange sounds as saliva and s*men mixed.

Supporting the back of my head firmly so I couldn’t lie down from exhaustion, he panted roughly while ej*culating in gulps. I looked up from below the man’s crotch with his p*nis in my mouth.

With an expressionless face, sweating like rain and steadying his breathing, he was maddeningly overwhelming. Decadent too, and excessively obscenely built. Had he always looked like this?

I had such thoughts while licking the instructor’s c*ck. He gently wiped away the s*men that had splattered near my eyes.

* * *

After that, I took a week off from exercise. I was honestly a bit worried about how to face him again, and I was actually suffering from muscle pain too. However, deep down I was also curious.

Whether he was satisfied too, whether another client was participating in his secret lessons while I wasn’t coming to exercise—I had many thoughts.

When I opened the door to the Pilates center after a long time, he happened to be sitting at the desk. 

Usually the manager who handles client management would always sit there and greet people, but he, wearing a wrinkled disposable black mask, stared blankly at me before hesitantly standing up to greet me.

After awkwardly receiving that greeting and leaving my coat in the changing room, I moved to the reformer room where the class was held when the time came. 

I spoke awkwardly even though I knew today’s class was just me, and moreover, that during this class, the other room’s class would end, leaving the center completely empty.

“Looks like today’s class is just me again.”

“Yes, client. The 11:40 class doesn’t seem popular. If even you stop coming, this class might get cancelled.”

“Oh no. This time is convenient for me though…”

“Then don’t miss class.”

His eyes above the mask were smiling gently, but somehow his tone was a bit firm.

“Well then, since you rested for a week, shall we do some catch-up exercise today?”

“Right away?”

Don’t we usually start with a warm-up? Why does it sound like he wants to jump straight to the main event?

“Is there anywhere that feels uncomfortable?”

“Ah… My lower back hurts a little.”

“Your lower back?”

He suddenly placed his hand on my lower back.

“Here?”

He caressed that ambiguous somewhere that’s too vague to call a waist—not quite the b*tt, not quite the pelvis. I nodded without realizing it.

“Did I pound you too hard?”

“Ah… More than that, it just feels like muscle pain.”

I added an evasive excuse, worried that if I said it was because of that, I might somehow fail to build internal intimacy with him again.

“Muscle pain needs to be covered with muscle exercise to heal quickly.”