A Different Kind of Training
It was almost an instinctive response that popped out of my mouth. Mom and my little stepsister were family, after all, so they couldn't help but wrestle with the moral side of things. But I wasn't a eunuch or anything—there was no way I was passing up a chance to get lewd with an Instagram goddess and famous trainer like Ra-hee noona.
...If anything, I welcomed it.
It was a dream come true for me, someone who'd secretly admired Ra-hee noona all this time. But when I thought about it a little deeper, there was a slight problem.
...Didn't Ra-hee noona have a boyfriend?
And a ridiculously handsome one at that. They'd been childhood sweethearts since middle school, and he worked as a trainer at this gym too. Naturally, they got along great. I'd even seen them flirting and working out together sometimes. No matter how stunning Ra-hee noona was, was it really smart to mess with someone who had a boyfriend? It could lead to a huge hassle.
"Come over here, Se-hyeon."
But the moment Ra-hee noona hooked her arm through mine, all those worries vanished from my head. She led me to a corner of the gym and spread out a mat on the floor, asking,
"What exercise do you want to start with?"
"...Whatever you recommend, noona."
"Then let's do a simple warm-up first?"
-Thud!
"Guh!?"
Ra-hee noona, with a smile on her face, suddenly shoved me down onto the yoga mat. Then she swiftly straddled me, planting both hands on my chest.
"Lick... ♡"
Her beast-like gaze as she licked her lips made it feel like she was really about to devour me. And on top of that.
M-my tits are right in front of me...
Ra-hee noona's cleavage, dizzyingly close as she sat on top of me, jiggled right before my eyes. Sweet sweat scent wafted from the beads of perspiration gathered in her cleavage, making my head spin.
"Your dick's gotten huge."
Smoothly—one hand stroked my crotch. Just that stimulation made my hips buck, and her smile deepened even more.
"Whoa, it's rock-hard... ♡"
"Guh... Noona... if you touch it like that..."
"If you'd told me sooner you had such a great cock, I would've milked it for you every time you came to the gym. ♡"
Ra-hee noona stared at me with eyes like she wanted to eat me alive. Her cleavage fully exposed through her sports bra was incredibly seductive and sexy. Meeting that gaze, I felt like prey caught by a predator—completely frozen. With our bodies overlapping on the mat like this, I could feel her body heat directly, and her warm breath tickling my nose was making my mind go hazy.
Is this heaven...?
The twisted common sense world was the best... My dick throbbed hard.
"Have you ever tried sex training?"
"S-sex training?"
Was that the thing where people post lewd stuff on SNS? But no.
"Yeah. Sex Training. It's all the rage these days. Great for fixing premature ejaculation, and it helps with diets for everyone, young or old."
So sex training was short for Sex Training. It was a pretty unfamiliar term, but it must've naturally emerged with the world's changed common sense. Ra-hee noona patiently explained that it wasn't just plain sex—it focused on strengthening core muscles between partners, improving premature ejaculation, and more, making it one of the best workout methods.
"Let's do a little warm-up first?"
Grind—
Grind—
Ra-hee noona rocked her lower body back and forth. Her prominent pussy mound, outlined sharply through her tight leggings, rubbed against my bulging pants. Scorching heat poured from between her legs. It felt like that area had a totally different temperature.
"What the—Se-hyeon, you're getting even harder?"
"N-noona keeps grinding like that..."
"Oh yeah? Hah! ♡"
Just as I tried to say something, Ra-hee noona suddenly leaned down, and my lips were blocked by something warm and moist.
"Mmph!?"
"Smooch, slurp... ♡"
I panicked at the sudden kiss, but our lips were already glued together. Like a beast pouncing on prey, Ra-hee noona covered my lips, staring at me with heated eyes as she sucked on my lips and tongue, sharing her warm, wet breath.
This is my first kiss, but...
No regrets. If anything, my heart was pounding.
"Hah... ♡"
This time, Ra-hee noona's tongue invaded my mouth, stirring wildly inside. The sticky saliva that wasn't mine filling my mouth felt so novel. Incredibly hot and fragrant... I'd seen scenes in dramas or comics where girls caught off-guard by a surprise kiss froze without resisting, and now I got why. Her sweet saliva and breath flooding in made my head fuzzy—I couldn't do a thing.
"Pha~ ♡"
After sucking on each other for a good while, our lips finally parted as Ra-hee noona let out a hot breath.
"How was it? Felt good?"
Nod nod—I hurriedly nodded. She'd stolen my first kiss out of nowhere, but it was pure bliss—no regrets at all.
"Okay, stretch your legs out straight."
"L-like this??"
"Yeah, good boy. Chu ♡"
Smoothly—As I stretched my legs out like she said, Ra-hee noona pecked my cheek in approval, then yanked down my pants and underwear in one go. My cock, pent up and raging, sprang up elastically.
"Whoa... what is this?"
Ra-hee noona's already big, pretty eyes widened even more at the sight of my dick. Sure, compared to the other guys at this gym, I didn't have much muscle, but I was confident mine was the biggest cock around.
Of course, up until now, without a girlfriend, I'd never had a chance to use it.
But.
Things are different now.
I looked at Ra-hee noona and asked,
"What should I do next?"
"Just lie there. Since you said you've never done sex training, I'll teach you step by step. But damn, your dick is ridiculously huge... What's the exact length in centimeters?"
"Uh, no idea? Never measured it..."
"What? You're 23 and you've never had a dick checkup? Don't they measure dick specs during regular health checkups?"
Hmm... Another weird common sense bomb. I decided to just play along vaguely.
"It's been so long since my last health checkup, I don't really remember... Was it during military service?"
"Sigh... They usually check thickness, length, ejaculation volume per shot, girth, endurance—all of it during a dick exam. Alpha males even post their results on SNS for certification. Hey, how are you gonna live as an adult guy without knowing your own dick specs?"
Felt like I was getting nagged... But thanks to her, I learned one more piece of common sense. In this twisted world, dicks were apparently treated like a spec to evaluate.
Made sense based on my experiences so far, but hearing it still made my heart race.
With mine, I've gotta be top-tier, right?
Lifelong virgin or not, I was confident in my size. A little over 20cm, with stamina that could handle three jerk-offs a day and still want more. Top 1% easy?
"Go get a spec check at a health center or designated hospital later. It'll help a ton when job hunting if you know your dick specs."
Stroke—
Stroke—
"Well, with a cock like this, you'd get a free pass anywhere... ♡"
"Guh..."
Maybe because of the kiss, blood was rushing to my dick so hard it hurt. I wanted to blow a load right then.
"Can I suck it once?"
Then Ra-hee noona dropped a bombshell. I met her eyes in shock.
"S-suck it?"
"Yeah. Like a prep exercise before sex training starts. Honestly, it'd be a shame not to suck a huge dick like this."
Ra-hee noona saying something like that... No way I'd refuse an idol-level beauty begging to suck my dick. With a mix of anticipation, I nodded.
"Sure. Do whatever you want, noona..."
"Hah...!! ♡♡"
Before I even finished, Ra-hee noona's expression flipped to a vulgar grin, and she dove onto my cock.
"Slurrrp! Sluuurp... ♡♡"
Right off the bat, sucking my dick. Her hot mouth clung to it, hollowing her cheeks. It happened in an instant.
"N-noona?"
Looking down in confusion, I saw Ra-hee noona with eyes rolled back in ecstasy, slurping my cock like a maniac.
"Mmph, sluuuurp ♡ Mmm, so thiiiick... ♡"
"Guh! Noona, too intense...!!"
"Sluuuurp, schluuuurp... ♡"
I'd said she could suck it, but I didn't expect her to go full throttle from the start. Ra-hee noona showed no intention of going easy—cheeks hollowed, eyes rolled up, she poured all her effort into devouring my thick cock.
"Slurrrp, mmm... sluuuuurp ♡"
She didn't seem super experienced—just going at it wildly. Her pretty eyes rolled up vulgarly as she glared at me, her tongue motor-boating my glans inside her pointed lips. She was dead serious about this blowjob.
"Mmph, sluuuurp, haaaah... "
Slurp slurp... ♡
This is way too intense for a warm-up...
One slip and I'd cum. Ra-hee noona, lost in ecstasy sucking a cock that wasn't even her boyfriend's, was too hot. Unthinkingly, as the urge to cum built, I grabbed her head.
"Guh... Noona...!"
"Mmph!? Gulp... ♡!?"
Ra-hee noona, eyes locked on my dick in a trance, looked up in surprise as my swelling cock started poking her throat from the excitement.
"Mmph! Gack... ♡!?"
Her face twisted in distress, nostrils flaring. But the ejaculation that had started couldn't be stopped.
"Sorry! I'm gonna cum!"