Chapter 4

On March 22, 2026. tripleS had a rare off-day after wrapping promotions, no music show, no fansign, just dorm downtime before prepping for the Asia tour kickoff. Most members scattered: some shopping in Gangnam, others napping. Yooyeon texted you at noon sharp.

"Come to the rooftop garden. Bring the small tripod. Wear something easy to unzip."

The building's private rooftop was staff-only, high walls, potted plants, a tiny greenhouse bubble for winter herbs. Sun poured in through glass panels. She waited in a loose white sundress (no bra, thin cotton panties visible when wind caught the hem). Innocent rabbit mode activated.

She'd set up a folding chair facing the city skyline. On a small table: her phone, lube, a slim vibrator, blindfold, noise-canceling earbuds, and a notebook.

"Experiment time," she announced brightly, like announcing a study group. "I read online that sensory deprivation makes orgasms 300% stronger. We're testing it. You film and observe. No touching me until I say."

She sat, spread her legs wide on the chair arms, dress rucked up, panties pulled aside and slipped the blindfold on. Earbuds in. World gone. She couldn't hear traffic below or your breathing.

First she teased herself slowly with fingers, narrating in that soft, curious voice.

"Pressure here... circles... mm, clit swelling already... inserting one finger, wetness level high today..."

Then the vibe. Low buzz. She arched, thighs quivering, but kept clinical.

"Setting to medium... internal pressure building... estimating 4 minutes to first climax..."

She came quietly at first, body jerking, a soft "ah~" escaping, then harder the second time, squirting a little onto the chair seat. Notebook forgotten; she just rode the waves.

Only then did she pull the blindfold halfway up, eyes glassy but focused on you.

"Data collected. Now... the real test. Call the maintenance guy. Tell him the greenhouse lock is stuck. When he comes up, don't speak. Just point."

You hesitated. She pouted cutely.

"Please? For science. And because I want to feel a stranger's cock while blind and deaf again. It'll be different data."

The guy arrived, mid-30s, toolbox in hand, confused. You gestured silently toward her. She was back in position: blindfold down, earbuds in, legs open, dress hiked, pussy glistening from her solo session.

He froze. Looked at you. You shrugged like she asked for it. He dropped the box, approached warily, then eagerly when she reached blindly for his belt, guiding him with small tugs.

She took him in her mouth first, slow, exploratory licks, humming around him like tasting a new flavor. Then she pulled him closer, legs wrapping his waist, guiding him inside raw. No words, just her muffled moans vibrating against his skin as he thrust.

You filmed close: the way her blindfolded face tilted toward every sound she could faintly catch, how her walls fluttered visibly when he hit deep, her fingers digging into his arms like anchors. She came twice more, once clenching so hard he groaned and finished inside her with a shudder.

When he pulled out, cum leaking, she finally removed the blindfold and earbuds. Blinked up at him sweetly.

"Thank you for participating in the experiment. Results: deprivation + stranger = intense squirting. 8/10. Would repeat."

He left dazed. She turned to you, cheeks flushed, notebook in hand scribbling.

"Your observations?"

You were rock-hard, silent. She smiled that pure, rabbit grin.

"Good data. Now phase two: you get to use me while I'm still sensitive and full of him. But..." She produced handcuffs from her bag. "Hands behind the chair. No cumming until I count to 100 out loud. If you do there will be a penalty, you will watch me text the tour backup dancers later without joining."

She cuffed you to the chair back, straddled you reverse, dress still on, just lifted, sinking down slowly onto your cock through the slick mess.

"Feel that? Slippery... warm... his cum lubing you..." She rocked languidly, counting in breathy Korean.

"Hana... dul... set..."

Every ten she clenched deliberately, giggling when you bucked. By 70 you were begging. At 100 she sped up, riding hard until you exploded deep, adding to the mix.

She uncuffed you, kissed your forehead softly.

"Best result yet. You lasted longest under restraint. Proud of my boyfriend."

She stood, let the dress fall back into place, cum trickling down her leg, packed her "lab equipment" and linked arms with you.

"Dinner? I want sushi. Uni is in season... and maybe later we can test temperature play with ice from the convenience store. Or exhibitionism on the subway home. Your choice this time."

She skipped toward the elevator, still the group's visual goddess, leader, Ewha smart girl, now humming happily, already brainstorming the next "experiment" in her head.

And you followed, because in her wild, insatiable world, you were the constant variable she kept returning to. The one who documented every discovery.