Archive of Our Own

“Doc, oh god,” Stone moaned, “It’s so much.” 

Robotnik held his breath and waited, stilling his hands. He watched the muscles in Stone’s stomach tighten, he watched his bare chest heave. He was wondering whose heart was beating faster, his or Stone's.  

“Oh god,” Stone breathed quietly, "Oh. Oh, Doctor."  

They’d been at this for a while. The Doctor honestly wasn’t sure how long. As he looked at his partner, a slight discomfort started to creep through his body, starting just behind the sternum.  

“Nnnnn,” Stone grumbled, shifting his hips slightly.  

That was his signal to move.  

“Oh, please,” Stone groaned, drawn out, beginning to wear thin, eyebrows furrowed with want.  

Robotnik thought back to how this had all started.  

They had been sitting at the table in Stone’s condo after dinner, sipping wine.  

“Take it farther than you think is okay,” Stone had said firmly, “Take it too far.” 

The Agent squeezed his hand reassuringly.  

“I – I don’t know, Stone,” he replied, breaking eye contact.  

“Do you trust me?” Stone asked.   

“Yes,” Robotnik replied, almost indignant at the implication.  

“Then you know I’ll stop you if it’s too much,” Stone pressed, “I want you in full boss-mode. I want you to not give a fuck.” 

Stone searched his partner’s face and saw a level of uncertainty in his eyes, in the tension in his jaw.  

“I want you to act like you don’t give a fuck,” he amended, “Like you used to.” 

Robotnik stared at him silently, feeling the Agent’s thumb brushing over the back of his palm gently. Though he wasn’t always proud of how he’d acted before they entered into a relationship, Stone didn’t seem bothered. Often, it seemed quite the opposite.   

“Stone,” he breathed quietly, hesitating on his next thought.  

He was interrupted by Stone pressing their foreheads together, a strong hand on the back of his neck. The Doctor closed his eyes and leaned in to the feeling.  

“I trust you,” Stone said quietly.  

“Mmhmm,” Robotnik sighed.  

“And you trust me,” Stone continued.  

“Of course,” Robotnik replied, opening his eyes.  

“Will you do this for me?” Stone asked, holding his gaze, “I can’t explain it, but I need it.” 

The Doctor could see it in his eyes, he could see the need there. A little fire flickered to life within him at the sight.  

“And remember, you have a say to stop it at any time, too,” Stone said, “It always goes both ways.” 

Robotnik squeezed his hand.  

“Yes,” he replied immediately, suddenly very certain, “I’ll do it.” 

That was how they’d ended up here, Robotnik fully dressed, Stone completely naked, hands tied above his head, looped around the headboard in an elegant knot, bound from wrist to elbow. The ropes were soft to the touch and a vibrant shade of red, standing out against his glimmering brown skin. The Doctor drew in a breath and trailed a finger of his free hand down his stomach, slowly into his pubic hair, watching him flinch in anticipation.  

“Look at you,” he purred, “All wrapped up like a present… I think I’ll wait a little longer to unwrap you. You know what they say about anticipation.” 

He dragged his finger lower, eyes lingering. Earlier in the evening, he had tied a ribbon in an ornate crisscross, starting at the base of Stone’s cock. The ribbon finished off in a neat bow just under his cockhead, which was looking flushed and wet.

"That it makes everything sweeter," Robotnik uttered, completing his previous thought.   

Next to the silky black ribbon was a matte black silicone ring that encircled the base of Stone’s cock and his balls, drawing them up tight against the underside of his shaft. At his ghostly touch, Stone’s hips stuttered a broken rhythm. With his other hand, Robotnik held a little cordless remote. He dialed the intensity up again, like he had many times tonight. He heard the crescendo of the soft buzz that emanated from inside his partner. Stone threw his head back and moaned, the knobby, ribbed vibrator inside him whirring to life once again. He clenched around it without restraint.  

He wished he could see, but he knew it felt better when he couldn’t.  

At the beginning of the evening, Robotnik had tied a wide silky black scarf over his eyes, folded double so he couldn’t see through it. Then, he’d tied him to the bed. Stone had lost all sense of time. It had at least been a few hours. A few hours of hard teasing, of the Doctor stroking him, fucking him with a toy, driving him right to the brink and then pulling back, pulling his hands away, killing the vibration of the toy abruptly, yanking away all the pleasure he was feeling in a devastating, dizzying shock. The Agent was nearly in tears. It was just too good. Each denial was glorious.  

Since he’d been requested in “full boss-mode,” Robotnik was wearing a heavy black lab coat that he often wore in the hangar, the one with the off-center buttons that went down the right side of his torso. He wore a pair of mid-forearm rubber gloves, thick and black. Though he didn’t need them tonight, he wore his glasses, the pair with slight magnification for circuitry work. They were simple, with somewhat chunky black plastic frames. He thought it only appropriate, since Stone was his little experiment tonight. He knew Stone liked his glasses. He’d told him so.  

At the beginning of the night, Stone’s eyes had lit up when he first saw Robotnik in this ensemble, gaze quickly going soft and half-lidded. He’d obviously liked what he saw, and the silent flattery stoked the Doctor’s fire.  

His thumb grazed the dial on his remote and turned up the vibration a bit more. He licked his lips as Stone’s thighs visibly tensed. He pressed one of the buttons, changing the vibration pattern to one that started low and gradually intensified before dropping back down again, a delicious bell curve.  

“Oh my god, oh my god,” Stone breathed, rocking his hips down against the bed.  

He could feel the pre-cum dribbling down his shaft and flinched. He was glad that Robotnik had lifted his hips earlier and put down a towel. He was shivering all over, completely overstimulated. He felt almost as though he had a fever, and was having one of those strange dreams one often had when their temperature ran hot.  

“Oh, Agent,” the Doctor mused, “I can’t tear my eyes away. You look delicious. Watching you fuck yourself with no hands… Oh, it’s quite a sight.” 

He watched his partner fuck himself down against the mattress and bit his lip. He reached down and gently grasped Stone’s balls in his hand. He stroked his thumb down the taut seam and sighed noncommittally.  

“Agent, are you doing to give me a nice load later?” he asked, tightening his grasp, tone going a shade more threatening, “Don’t disappoint me.” 

The Agent gasped. He wanted to dig his heels into the bed, to bend his knees, but his legs had been spread and tied at the ankle. He flinched and cried out when Robotnik squeezed the base of his cock hard. 

“Doctor, please,” he begged, voice broken “Please.” 

Robotnik felt a lump in his throat looking down at Stone, an uncomfortable crawly feeling in his belly. He knew that “please” wasn’t the safe word. He knew that his partner would only opt out by using their predetermined safe word. Stone had never once faltered to throw in the towel or hit the pause button when he needed to, but he sounded terribly desperate.  

Do you trust me? Stone’s voice echoed in his head.  

Of course I do, Robotnik thought to himself, straightening back up.  

“I love it when you beg,” he said, steeling himself, “But you know it won’t get you anywhere.” 

“Ohhh,” Stone despaired, laying limply against the bed, hips still moving.  

Robotnik began to move his fist up Stone’s shaft, listening to his shaky, dry breaths.  

“No, no, Stone,” he tutted, “You’re not done until I’m done with you.” 

He stroked his cock with a firm grip, feeling the damp satin ribbon slipping through his fingers. Stone’s cockhead was positively weeping, a sticky clear bead of fluid slipping out. The Doctor resisted the urge to lick it away, to taste it on his tongue.  

“You’re my experiment tonight,” Robotnik purred, “And tonight, we are testing limits.” 

Stone let out a dry sob underneath him, biceps straining against his bonds. He admired his muscles shamelessly with an approving shake of his head, one that his blindfolded partner couldn't see.   

“You’ll cum when I say so and not a second before,” he continued, voice low and professional, bordering on sinister.  

He put his remote to use and changed the vibration pattern again to one of quick pulses.  

Stone cried out loudly and arched up off of the bed, trying not to work his hips up against the Doctor’s teasing hand. If he fucked himself against the toy, it only meant more friction on his desperate cock. He was lightheaded. He was sure that if he could see, he would be seeing through tunnel vision.   

“It’s so good!” he moaned, “Oh god, it’s so good! Fuck!” 

Stone felt his eyes rolling back, suddenly so close to his climax again. He'd lost count of how many near-orgasms he'd had tonight. He felt his hips moving automatically, fucking up into Robotnik’s rubbery grip, only prolonging his own torture. Everything felt so tight, he was so tense all over. A fire was raging in his belly. He wanted to cum so bad. He was aware that his breaths were coming in short, pitched gasps, on the border of sounding pained.  

Robotnik could feel Stone’s legs shaking and knew that he was close. As quickly as he had started, he gripped Stone’s cock hard around the base, stopping his climax in its tracks. The Agent threw his head back and let out a staggering shout, halfway between crushing agony and searing pleasure. The Doctor watched his fingers curl into claws and then into clenched firsts at the overload of sensations.  

Robotnik immediately tucked the remote into his pocket. With his freed hand, he took hold of the base of the toy and began fucking Stone with it, his fist still wrapped tightly around the base of his cock, feeling it pulsing in vain. Stone felt his prostate being hammered by the vibrating toy, the pleasure of it diluting the sharp ache of his denied orgasm. He nearly screamed when he felt Robotnik’s warm, velvety tongue lapping the trickle of fluid away from his cockhead.  

After a long lick, Robotnik straightened at the waist and looked down at his partner, a quivering, heaving mass on the bed. Stone’s neck was arched and all of his muscles were tensed. He felt the hair on his forearms raise and a deep, burning all through his hips. He was gasping, swallowing dry. Robotnik waited to hear what he would say, hands clasped together tightly.  

“Doctor, please,” he begged, clearing his throat, “Again.” 

A chill went through him when he heard Robotnik issue forth a deep laugh. He trembled when he felt those deft fingers toying with the quick release on the cock ring.  

“Still have some more in you, hm?” he asked teasingly, suddenly pulling his hands away, pushing his glasses up his nose.  

Stone was floating in space again, unmoored without the physical contact to hold him to this world.  

“I’m gonna die,” he groaned, tossing his head from side to side, trying to gather his bearings without the use of sight. 

Despite his dramatic statement, he was grinning dizzily.  

Robotnik let out a little breath he didn’t know he’d been holding when he saw that smile.  

“Now, Agent,” he said, “You knew that this experiment would occur outside of working hours. You knew that this was not a required component of your job. You reviewed the informed consent. You waited the twenty-four hour waiting period. You signed the informed consent. You knew exactly what you were getting in to. And you know you’re not going to die.” 

“Uhh,” he moaned, unable to stifle a woozy laugh as his head hit the pillows limply, “But it feels like it.” 

“You really think I would let you?” Robotnik asked coolly, “You really think, Agent Stone, that after having a taste of all this,” here he ran his fingers lightly down his chest, “that I wouldn’t want to come back for more?” 

Again, a chill ran through Stone’s exhausted body at his words. He’d been denied so many times tonight. He wanted to cum, and he wanted it terribly, but being denied was like being consumed by flames over and over and still coming out the other side alive. Ragged and singed, exhausted, but alive. Robotnik's words poured over him like gasoline, reigniting the tired, guttering flames.   

“Oh, no. You’re not going anywhere. We’ll need more data about the limits of the human body. We’ll need more trials,” Robotnik continued, voice starting to raise as it often did when he discussed something he was passionate about, “Yes, this will take several sessions to garner sufficient findings. We’ll need temperature tests. Stress tests. Vitals information. Fluid samples.” 

The Agent felt his guts clench at the last item.  

“In short, you will survive and you will do this again. We have so much left to learn,” Robotnik hissed, clenching his rubber-clad hand audibly in triumph, “Understood?” 

Stone realized that he was practically gasping for breath and wasn’t sure how long he had been. He swallowed to combat his dry throat.  

“Yes, Doctor,” he said, as professionally as he could manage.  

“Very good, Agent,” Robotnik replied curtly, taking up a clipboard from the bedside table, “Now, let’s discuss the findings.” 

He took a pen from the pocket of his lap coat and clicked it, giving Stone a little audio clue to tantalize his mind. He pulled off one of his gloves carefully, tucking it under his arm. He would need his fingertips shortly. The squeak of rubber on rubber confused Stone, as foggy as his mind was.  

“Of course, Doctor,” he said dizzily.  

He could practically feel those eyes all over his body. Indeed, Robotnik was taking in the sight, looking at his tired, muscular frame, his glistening skin, slick with the sweat of prolonged attention. It was undeniable – Stone had a gorgeous body, and it was a really treat to be able to ogle him unseen, for Robotnik to be able to take his fill of it unobserved.  

“So, Agent, how did this orgasm compare to the last one in terms of intensity?” he asked clinically.  

“Extremely intense,” Stone said, “I’m dizzy. A little lightheaded. My heart is still racing. This one had my hair standing on end.” 

“I observed what appeared to be extreme muscle tension immediately after. Can you confirm?” Robotnik asked, scratching his pen against the paper audibly. 

“Yes. Straining all over. Straining against the ropes,” Stone said, trying to slow his breathing, “It felt like I… Like I had to manually unclench everything after. My – uh – arms were so tense they were shaking.” 

The Doctor smiled, finding it very admirable that the Agent was carrying on so well, particularly since the vibrator was still working inside of him, buzzing away in quick little pulses. 

“Your endurance is slipping but that’s to be expected,” Robotnik replied, looking down at his wristwatch, “You’ve clocked in a few minutes under last round.” 

The Agent made sort of a disappointed hum.  

“It’s perfectly normal, Agent,” Robotnik said.  

It was a tone that Stone hadn’t heard in a long time – the words perhaps meant to be comforting, but the tone aloof. He used to hear this tone of voice periodically before they became an item, at moments when his boss would almost comfort him while maintaining a more-than healthy level of emotional distance. This was all so immersive that it made his guts churn.  

“Now,” the Doctor pressed on, “You’ve been blindfolded for an hour. How are your bearings? Do you know where I am?” 

“I have no idea,” Stone confessed, “I’m completely disoriented.” 

After putting the blindfold on Stone, Robotnik had slipped out of his shoes, padding around the bedroom barefoot, making himself harder to hear.  

“Hmm. Interesting,” Robotnik said, “I am going to move and will signal you when I’m ready. Let’s test your orienteering.” 

He moved silently down to the foot of the bed. Stone strained to hear him, but his sense of personal orientation was all but gone. He thought about how your other senses were supposed to get stronger when one is reduced. He was sure that the several denied orgasms he’d endured were affecting him more than the blindfold.  

“Where am I, Agent?” Robotnik asked.  

“I – I’m not sure, Doctor,” he replied, turning his head from side to side out of habit.  

Robotnik reached down with his ungloved hand and grabbed the arch of Stone’s foot, making him jump.  

“Well, at least your reaction time is good,” he said dismissively.  

This was very purposeful. His hand lingered on Stone’s foot, feeling the temperature of his skin. He wanted to make sure that his circulation was sufficient after having been tied up for so long. He let go and purposefully scratched his pen loudly, making notes on his clipboard.  

Was this a real experiment? No.  

Was this going to keep Doctor Robotnik from taking sufficient notes? Also no.  

The sound of the pen scratching on paper was deafening to the Agent. It made his skin crawl pleasantly.  

Robotnik walked silently to the head of the bed, this time not speaking. He reached out and took hold of Stone’s hand, tied up above his head. Though his motions were slow and deliberate, it still startled the Agent, evidenced by a little flinch and a quiet gasp. His skin was warm, the color natural. He lingered before pulling away, making a note that Stone’s overall circulation was good.  

Robotnik audibly clicked the pen against his clipboard and made a point of flipping through the pages there. He wasn’t really reading anything he’d written. He just wanted to make Stone wait, to make it feel real. He set the clipboard down on the nightstand.  

“Now, let’s move on to the next phase of tonight’s session, shall we?” he asked clinically, pulling his glove back on with a snap.  

Stone let out a weak whimper but nodded all the same.   

“Don’t worry, Agent,” Robotnik said, in a dramatic semblance of pity, taking Stone’s chin roughly in his hand, “This will be the final phase of the night.” 

He felt a wave of genuine pity wash over him as Stone let out a harsh breath and a little whine. He knew that Stone wanted more, but he wasn’t sure how long he could keep this up. It was so visceral, denying him and watching him squirm and shudder and beg, right on the edge of pain. Robotnik admitted inwardly, with a touch of guilt, that it was also arousing in its intensity.  

The Doctor had done plenty of research on edging beforehand, he knew all the necessary safety protocols and made sure to take them. There were blunt-tipped bandage scissors nearby in case the ropes needed to be cut. He had a tall glass of water waiting, and a little basin of water with a washcloth nearby. In case Stone lost consciousness, he had a little container of smelling salts on the nightstand, though he hoped with all of his being that it wouldn’t have to come to that.  

Stone’s words echoed in his head. 

I trust you. 

And you trust me. 

Will you do this for me? 

He nodded and squared his shoulders, ready to put on the act again. He knew that he could tap out at any time, too, and that was a great comfort. The safe word worked both ways. Right now, as he looked down at Stone’s spread, tied, tense, glorious body, at the half-smile on his mouth that betrayed the heaving of his chest. He knew that he was enjoying it. He wanted to give him what he wanted, as much of it as he could handle. 

Everything’s fine, Robotnik reminded himself, it’s all a game.  

This next part, they had not discussed. Stone had left much up to the Doctor’s interpretation. Robotnik quietly unzipped his trousers, slipped them down. He’d forgone a belt. Too noisy. He undressed in virtual silence, watching Stone’s face, sure that he was trying to figure out what was going on from beneath his blindfold. As this element had been up to only his discretion, he felt a slight flutter of nervousness.  

Robotnik stood by the side of the bed, naked from the waist down, eyeing his partner. He reached down with careful fingers and slowly untied the bow around Stone’s cock, watching him shiver and buck. He meticulously uncrossed the ribbon, leaving only the loop around the base. Instead of just unlooping it, he pulled the ribbon from one end, letting it slip away inch-by-inch, Stone feeling the full length of it, letting out an inelegant sound.   

Stone gasped several times at the sensation of the ribbon moving against his oversensitive cock. He closed his fists tightly, unable to grasp at anything for leverage with his tied hands.  

“Oh, Doctor!” he moaned, “It’s so good. Oh, please. Please, please, please…” 

He wasn’t even sure what he was begging for at this point. Just more. More of anything. More of everything.  

Robotnik was careful to withdraw contact entirely again. As badly as he wanted to touch his partner, he knew that sensory deprivation was an important part of this scenario. He clasped his itching hands in front of himself dutifully.  

“Look at you,” he said softly, “So desperate to finish. Oh, Agent, you look good.” 

Stone squirmed and bit his lip, the praise sending little bolts through him all over.  

Robotnik took up the remote again and changed the cadence of the vibrator from pulses to a sort of gentle, unceasing bell curve, endlessly undulating. He watched Stone’s shoulders relax into the bed. He tucked the little remote into his coat pocket again for later. 

“Now, we’re not done yet,” he assured, “I need you on your A-game, Agent. I desperately want for this experiment to be a success, but that relies heavily on you. Do you understand?”  

“Yes, Doctor,” Stone said, in a lewd facsimile of his work voice.  

Robotnik surveyed the items on the nightstand, running his gloved finger along the edge. He stopped at the little bottle of lubricant and picked it up purposefully. He turned back toward the bed, the floor cool under his bare soles.  

He drew in a deep breath and began to slowly drip the lube in a thin, halting stream onto Stone’s cock from a few inches above. The cool liquid made him hiss and flinch, arching up off of the bed.  

“Is that cold?” he asked plainly.  

“Uh-huh,” Stone agreed, straining his neck.  

“It’ll warm up,” Robotnik replied.  

He sat on the edge of the bed briefly, Stone aware of his weight on the mattress, giving him a point of reference. Robotnik wrapped his gloved fingers around Stone’s cock and spread the lube all over, slicking him generously from base to tip. The Agent let out a shaky, high moan. The lubed rubber glove was achingly slippery and he was so turned on, all of his nerve endings crackling with unfathomable amounts of pleasure.   

“Ooh, you’re so sensitive,” Robotnik said, pulling his hand away from Stone’s hard, flushed cock, “Now, remember. You aren’t to finish until I say.” 

“Yes, Doctor,” Stone replied with a thick swallow.  

“Not that you have much of a choice,” Robotnik added darkly, toying with the ring still clamped tightly around the base of his cock.  

Stone groaned at the contact. The Doctor grinned and stood again. This was the part he’d been waiting for. He carefully climbed onto the bed and straddled Stone’s hips, hovering above him.  

“Oh!” the Agent gasped in surprise.  

He wasn’t sure what was about to happen, but his mind was racing with possibilities. Perhaps a hand clamped around his throat, or holding his head back, some light choking. His throat went dry when he felt bare skin against his legs.  

Robotnik used his slicked hand and reached back between his legs. He pressed his lubed fingers against his hole, testing himself. He’d stretched himself carefully before Stone had came over, in preparation for this encounter. Once satisfied after a bit of light probing, he took hold of Stone’s cock and sank down onto it relatively quickly, bottoming out with a relaxed grunt.  

“Oh my fucking god!” Stone cried, clenching his hands tightly, pulling against his bonds.  

He instantly knew that it was Robotnik easing down onto him. He was not expecting this. Usually the Doctor’s body was warm and slick and welcoming, but tonight, knowing that he had zero control, after having been mercilessly teased for ages beforehand, it was torturous. His mouth was hanging open, droning out a long, low, hoarse moan.   

Robotnik pushed himself down into Stone’s lap and held in a mewl of his own. His hands plucked open the buttons of his black lab coat, exposing his bare torso underneath. He considered shrugging the coat off, ditching the high rubber gloves. He’d lifted the coat from his shoulders when he thought of how Stone would like it if he left it on, and then dropped the fabric, leaving it in place. Again, he pushed his glasses up his nose.  

“Still think you can hold out for another round?” he asked.  

He could feel the Agent shaking underneath him.  

“Yes, Doctor,” Stone said, his tone perfectly professional, though feeble.  

Robotnik grinned wide.  

“Now, that’s what I like to hear,” he replied hungrily.  

He began to move his hips slowly, taking Stone’s cock base to tip, deep and slow. He breathed out through his nose and looked down at Stone. His mouth was hanging open in disbelief. He admired him for a long moment, looking at the handsome bits of his face that were visible beneath the blindfold, looking at how the neatly crisscrossed vermilion ropes stood out vibrantly against his warm, beautiful skin. 

“Phase two, Agent,” Robotnik said, “Thoughts so far?” 

He was being mindful to keep his tone even and steady, to remain in control of his own voice, even as Stone's cock filled him up so pleasurably. He wasn't sure how Stone was holding out this long. He'd only been sat on his cock a moment and he was already vying for a quick, intense climax. 

“Ah, um,” Stone stammered, “Elevated heart rate. Um, increased muscle tension. Oh.” 

“Yes, but how does it feel?” he pressed.  

“So fucking good, you have no idea. Oh my god,” Stone rattled off, panting, smiling, feeling himself gradually being reduced to a puddle.  

“I’d ask you to hand me my clipboard, but, you know,” he teased, eyeing the Agent’s bound wrists.  

Stone laughed a little, leveling off into a grunt when Robotnik started taking his cock a little more slowly, grinding in his lap. The Doctor allowed himself a soft sigh, mainly for the benefit of his partner, watching his jaw tighten at the sound.  

He was rolling his hips in an excruciatingly slow rhythm, an easy grind that was filling him with a sort of languid pleasure. He looked up at Stone’s clenched hands, sure that he was applying just the right amount of pressure. He reached for the remote in his coat pocket, but decided to wait.  

Stone was sucking in breath through his teeth, halfway through a delirious grin and a devastated grit. Robotnik desperately wanted to see the rest of his face. He considered his options carefully before making a decision.  

“Ok, Agent, we’re going to make this a bit more difficult,” he purred, leaning forward.  

Stone groaned and rolled his shoulders, nodding, unable to formulate words. He wasn't sure what the Doctor meant, but he was ready for it.   

Robotnik leaned forward slowly, carefully.  

“Lift your head,” he whispered.  

The Agent obeyed and felt Robotnik’s fingers slip behind him, carefully untying the knot that fixed his blindfold. Stone felt is slip away from his eyes, blinking into the dim light of the room. Despite the mood lighting, it still felt too bright. He squinted his eyes to better focus on the sight before him.  

“Holy shit,” Stone breathed.  

Robotnik was seated in his lap, legs bare and spread, cock hard. As his eyes traveled higher, Stone felt his chest tightening, his breathing becoming more labored. The Doctor was still in his thick black lab coat with shiny black gloves up to his elbows, hands resting on his pale thighs. He was wearing his glasses, looking down at Stone with a sly, imperious look.  

“Like what you see, Agent?” he asked, passing his tongue over the surface of his teeth.  

Stone nodded, swallowing the lump that had suddenly formed in his throat. He felt himself clench hard around the toy that was still buzzing steadily inside of him, feeling the vibrations ripple through him as he did, resulting in a little spasm.  

“Good. That should make it a bit more difficult for you to hold out, hm?” Robotnik asked with a wicked grin.  

Stone’s head fell limply against the pillow with a heavy breath. He was overwhelmed, dizzy. He thought he'd been close earlier in the night, but now with Robotnik in his lap taking his cock so expertly, dressed like something out of his private fantasies, Stone truly didn't know how much longer he could hold out. 

“Oh, let’s fix that,” Robotnik said, noticing that he was staring up at the ceiling. 

He leaned forward again, using the angle to fuck himself slowly on Stone’s cock. He gathered the pillows beneath Stone's head and propped him up with care. The brush of the rubber glove against his cheek made the Agent quail.  

“There. Now you’ve no choice but to look,” Robotnik said, straightening back up, rocking his hips down against him, “There’s no escaping, Agent. Now, let’s continue the experiment.” 

“Oh, god,” Stone breathed, wringing his tied hands, “Doctor, it’s too much.”  

He was closer to the razor’s edge of ecstasy than he had been all night, between Robotnik’s slick, gripping heat and the gently undulating vibrator inside him. He rocked his hips slowly, up against the Doctor, then down against the toy. The sensations raised goosebumps on his forearms. He clenched his jaw and hissed out a difficult breath. He kept rocking his hips slowly, chasing a climax that was beyond his control.  

“Oh, this is too good to not record,” Robotnik said with a shrug.  

He braced his weight with one hand on the bed, leaning forward again, stretching his body to grasp the edge of the clipboard on the nightstand. He let out a breathy moan at the new angle of Stone’s cock, the tip hitting him differently. He held there for a beat before straightening up again. He clicked the pen with his thumb and put the tip to the paper.   

“Subject is exhibiting pupil dilation, shortness of breath,” he spoke, grinding down rhythmically on his cock, lifting himself slightly with each movement, “Ideomotor response noted in the hands and fingers. Tension in the neck and jaw.” 

“Doctor, it’s too much,” Stone whined, twisting underneath him.  

“Do you want it to stop?” Robotnik asked, looking down the bridge of his nose at him, just above the clipboard, “You know how to make it stop.” 

He lowered his weight into Stone’s lap, going utterly still, pinning him to the bed. The Agent’s hips squirmed underneath him, rubbing pleasurably inside him. He closed his eyes tightly and swallowed before opening them again, fixing Robotnik with a tired, wrought expression before his eyelids fluttered with pleasure.  

“No,” he gasped assuredly, “I don’t want it to stop.” 

“Very well, Agent,” Robotnik said, scribbling something else down before lifting his hips again and settling into an easy rhythm.  

“Oooh, please, please, please,” Stone whimpered, succumbing to the feeling.  

Robotnik grinned and reached into his coat pocket. He turned up the vibration of the toy slightly and watched Stone throw his head back with a shaky moan. The pressure building inside his body that had been steadily growing throughout the night was nearly as much as Stone could take, suddenly exponential. The Doctor couldn't tear his eyes from Stone's face, watching his brows lift and furrow in pleasure, watching his tongue dart out to moisten his parted lips.   

“Open those eyes now,” Robotnik purrred, almost comforting, but not quite.   

He opened his eyes slowly gazing up at him as he tucked the little remote away again. He sneered down at him as he pushed his glasses up his nose, halfway to a toothy grin. The gesture sent a little jolt through Stone’s guts.  

“You look so fucking sexy,” the Agent moaned desperately, “I wish I could touch you.” 

Robotnik fell out of rhythm for a fraction of a second, stretching his neck and letting out a soft grunt. He was never immune to praise and Stone knew it.  

“But how do you feel, Agent?” he asked, clearing his throat, regaining his in-control tone.   

“So fucking incredible,” Stone gritted between breaths, “There’s this – aah – pressure that’s been building all night. It’s just. Oh god. I feel like I’m on fire. Like I’m being consumed. Oh fuck!” 

He was moving his hips again, fucking up into Robotnik, being fucked by the ever insistent vibrator.  

“Keep moving your hips like that, you’ll only make it more intense,” Robotnik said, rocking back against him hard for a few strokes, “Remember, you don’t cum until I do.” 

Stone’s eyes rolled back and pushed his head into the pillow, feeling the ache in his core. Robotnik clicked his pen and put it in his coat pocket, tucking his clipboard under his arm. On the edge of the bed sat the bottle of lubricant, which he grabbed and flicked open with his thumb.  

He trickled a thin stream onto his cock, then a bit into his glove. He reached down, feeling the breathtaking slickness of the rubber against his most sensitive skin. He let out a drawn out moan, head slipping back, not holding back. He knew that Stone couldn’t take much more, and neither could he.  

“Watch, Agent,” he commanded, voice laced with pleasure. 

Stone’s eyes opened and he gasped at the sight. That heavy black glove slipping over the Doctor’s flushed cock, the open lab coat exposing his slender body, hanging down past his hips, clipboard clasped tightly beneath his arm. His brows were arched and determined, his grin calculated, but his eyes were venturing toward dreamy, glasses sliding down his nose.  

Stone groaned, biting his lower lip. He needed to cum. He clenched his hands helplessly again. He needed it so badly, but he knew that it would be better if he could wait just a little bit longer. His cock was throbbing, aching so sweetly. They’d gone the first few rounds without a cock ring. Then the blindfold. Then the cock ring. Now, this. 

He licked his lips as he watched that shining black glove slip over the hot pink skin. His stomach was all knotted up, listening to the wet, slick sounds, listening to the Doctor’s breathing, his soft moans, signaling that he was right on the edge, too. Through the fabric of his open lab coat, Stone could see his narrow chest heaving.  

Robotnik rocked harder into Stone’s lap, needing more, filling himself up with force as he stroked his own cock. He arched his back into the feeling, pumping his hips down harder, feeling Stone meet him halfway, hearing his ragged breaths, hearing the obscured buzzing of the vibrator inside him.  

Credit where credit is due, Stone was full of wonderful ideas. Robotnik had known this for a long time, but scenarios like this reminded him.   

“Oh, Agent,” he groaned, stretching his back, “I’m so close already. Your cock’s so thick. Mmm.” 

“Fuck,” Stone breathed quietly, "You're gonna make me cum." 

“And you look so good,” the Doctor continued, eyes half-lidded, “All tied up and at your wit’s end, muscles all tense, glistening, caught between me taking your cock and a toy inside you. God, I bet you want to cum so bad, hm?” 

“I do!” Stone gasped, hips jerking of their own accord.  

Robotnik fished the remote out of his pocket again with his free hand, cranking up the vibration again. Stone stiffened and made a choked sound, arching against his bonds.  

“You’ve been so good tonight. Just tell me when you’re ready and the experiment will be over,” Robotnik said, leaning his head back to keep his glasses from slipping again.  

“I can’t take much more,” Stone gritted, watching him intently, unable to look away. 

He sounded breathless, like his throat was nearly too tight to speak.  

“Just say when,” Robotnik grunted, paying special attention to his own cockhead, hips jerking against the intoxicating slickness of rubber against his most intimate areas.  

He was so close, and felt immeasurably closer when he looked down at gorgeous, alluring Stone. He rolled his hips harder against him, angling just right to hit his prostate with each stroke.  

“Fuck!” Robotnik growled, “Ohhh, fuck. That’s good.” 

After a few more strokes at that angle, he let his head fall forward, rutting down against the Agent. Then tension in Stone’s body was suddenly too much. It felt like he was collapsing in on himself, his vision beginning to go black at the edges, the world dematerializing from underneath him. Everything was searing, everything was hot, everything was tight, everything was too much and he couldn’t take it anymore.  

“I need to cum now!” Stone begged, “Please. Please! Doctor, please! I need it!” 

Robotnik immediately registered the urgency in his voice. He wasted no time, quickly reaching down between them, his clipboard clattering to the floor as he pulled the quick release on the cock ring. All it took was two more skillful rolls of his bony hips and Stone was there, pulse after hot pulse inside of him, filling him up with all of that prolonged desire, all of that agonizing pleasure, all of it until he didn't have any left, hips still surging away fiercely.   

And what is an experiment without a chain reaction? As Stone went over the edge, arching off the bed, crying out, gasping, struggling to hang on to his existence as the world seemingly tried to buck him off, Robotnik followed, finishing into the warm, slippery rubber of his glove with a shout, doing his best to keep both knees on the bed as Stone railed him from beneath.  

After several seconds of panting, he opened his eyes. Though his head was spinning, Robotnik knew that he had to get to work immediately. He looked down at the pearly white streaks against the black rubber and felt his stomach tighten, felt himself clench wetly around Stone’s softening, throbbing cock. Then he looked to Stone, whose head was resting against the pillows, chest heaving hard. He looked utterly blissed out, totally wrecked, miles away.  

He pulled the remote from his pocked and slowly dialed the vibrations down, lower and lower until the toy was completely off. With regret, he lifted his hips and pulled gently off of Stone’s cock, feeling him flinch sharply underneath him as he slipped out, obviously oversensitive. He whined in a way that made the Doctor’s heart ache.  

Now came the hard part.  

He climbed off of Stone’s lap and took to his feet, lab coat open, naked from the waist down, cum dribbling lewdly out of him and down the inside of his thighs. He composed himself and looked down at Stone imperiously.  

“That was sufficient, Agent,” he said seriously, working hard to take measured breaths, “Compose yourself while I go get some vials for the fluid samples.” 

He watched his partner’s eyes roll again, chest raising slightly off of the bed in an involuntary pleasure spasm. Robotnik turned his back on him and walked out of the room, closing the door behind him, immediately slumping against it for support, feeling himself sliding down as his knees started to give way.  

He let out a ragged sigh and allowed his breath to come in deep heaves again. He counted thirty seconds, positively dying to go back in and take care of his Agent. He knew that this last display would likely push this encounter over the top for him. The Doctor took a deep breath and opened the door wide again, stepping inside and peeling off his sticky rubber gloves, tossing them carelessly to the floor. Stone turned his head to look at him, eyes positively glowing with affection, his face glistening with a dewy sweat. He swallowed, trying to form words as he partner walked in.  

Without a word, Robotnik straddled Stone’s waist and began untying his hands as quickly as he could, taking both wrists into his own hands, rubbing where the ropes had left pink impressions, making sure his fingers were warm. He leaned in and kissed the younger man gently on his forehead. Stone’s eyes fluttered open again and stared up at him adoringly, flashing him brief smile before closing his eyes again, letting his head fall to the side.

"You've done so well," Robotnik encouraged in a soft, gentle voice, "I'm very proud of you, Stone."  

He’s fine, he assured himself with a sigh of relief.  

Next, with legs more unsteady than he cared to admit, he climbed off of Stone and sat again on the edge of the bed, untying each ankle and doing the same as he had with his wrists, rubbing where the ropes left their temporary stripes, feeling the temperature of his skin on the soles of his feet, on his toes. Once satisfied, he carefully eased the vibrator out of him and set it on the nightstand.  

Robotnik stood briefly, sidestepping his abandoned clipboard, stretching his back and shrugging off his lab coat, letting it fall carelessly to the floor. He sat on the edge of the bed and wiped the sweat from his brow, shaking the loose strands of hair from his forehead.  

He reached for the little basin of water, soaking a washcloth and wringing it out. He took the cool, damp cloth and rubbed it across Stone’s forehead, down his cheek. Again, Stone’s eyes opened slowly, appearing to take effort to focus on him. The Agent cleared his throat.  

“Was the experiment a success, Doctor?” he asked weakly.  

“Yes,” Robotnik said, unable to keep a wide smile from his face as he soaked and wrung the washcloth again, “Just taking some final mental notes.” 

Stone laughed weakly, rubbing one wrist with his recently-freed hand. The Doctor was an expert knot-maker, nothing ever too tight or painful. He always seemed to come out miraculously unchafed. 

“Subject is exhibiting signs of euphoria, delirium. Elevated body temperature. Exhaustion,” Robotnik listed, rubbing Stone's chest down with the cool cloth, feeling him shiver, “Test administrator is exhibiting similar signs.” 

Stone laughed again, an intense relaxation beginning to set in, feeling his physical body limply sinking into the bed, feeling his consciousness apparently floating a few inches above his physical body. He had edged before, but never anything like this. He was so hot, burning up from the inside out. The cloth that Robotnik was rubbing his body down with was doing wonders to cool him down.  

“Do you need a drink?” The Doctor asked 

“Yes, please,” Stone said, trying to push himself up, unsteady, dizzy.   

“No, no, no,” Robotnik cooed, pushing him down gently, “You need to rest.” 

He picked up the glass of water from the nightstand, slipping a hand under Stone’s head.  

“Let me help you,” he said quietly.  

Robotnik lifted his head gently and held the glass to his lips, giving him a few swallows of cold water. Stone drank it greedily, ravenously thirsty. The Doctor knew when to pull the glass back, giving him a moment to swallow before giving him a few more sips. He looked down at Stone’s flushed, tired face and felt his heart throb.  

“Easy now. That’s enough,” Robotnik said, easing Stone’s head back down onto the pillow and ruffling a hand through his hair.  

He set the glass aside and straightened up.  

“Tell me what you need,” he said, looking down at his wrecked partner.  

“You,” Stone said softly, turning his head to the side.   

An affectionate shiver overtook the Doctor suddenly, a hand coming up to cover his heart in an unplanned gesture. Suddenly, he couldn’t get into bed quickly enough. He walked around to the other side and laid down next to Stone. He sat back up for a moment to take off his glasses and set them folded on the nightstand.  

He coaxed Stone’s tired body over against his, back to his chest, and wrapped his arms around him. The Agent sighed against him and let his head loll to the side. Robotnik leaned in to kiss his temple before letting his head fall back against the stacked pillows, eyes closed.  

He had one arm wrapped around Stone’s rib cage, the other hand splayed loosely over his chest. His skin was damp with sweat, hot, just on the edge of starting to cool down. Robotnik knew that after intense scenes like this, he needed to use a gentle hand. He was content to stay there as long as he needed, already starting to slip into a doze. Stone’s body was a pleasant weight against his chest, breathing against him in a gradually-slowing rhythm.   

Indeed, the Doctor did doze, falling easily into a brief but heavy sleep. He woke up about twenty minutes later, Stone still laying limply against him. Finding that his hold had gone a bit slack, he tightened his arms around him again. Stone’s body was cooler now, his breathing deep and even. He was sleeping soundly.  

I’m sure you’re tired, Robotnik thought, looking at what he could see of his relaxed face.  

Again, he closed his eyes, but knew he would be awake for the duration this time. He let Stone sleep. He thought back to their initial conversation about this scene and how he’d felt about it. Of course, he’d agreed because they trusted one another and had a strong safety protocol in place. But later that night, Stone had texted him.  

Hey, I kinda got ahead of myself. I want you to be comfortable with everything we try. We don’t have to do it. I know it’s a lot.  

He responded simply and honestly: I’ll be more confident in the idea if we discuss it more. 

And discuss it they did. A few nights later, they sat facing one another on the Agent’s sofa, going through the ins and outs of almost everything. By the end of it, Robotnik was fully comfortable and confident with the scenario, having taken copious notes. He’d developed some of the scenario on his own in the lab later that night, wanting to make it just perfect for Stone. He smiled as he looked down at his partner again. Stone had wanted it to be perfect for him, too, and of course, it had been.

Having spent so many years alone, Robotnik was amazed at how quickly they'd fallen into a healthy habit of communication. He attributed all of that to Stone, who had been nothing if not patient and instructive as they grew to know one another as romantic partners.   

A short time later, the Agent began to stir, first with a deep inhale and then with a little stretch.  

“Hello,” Robotnik said quietly.  

Stone whimpered before slowly opening his tired eyes.  

“How do you feel?” the Doctor asked him, scratching his fingernails lightly through his chest hair.  

“Sublime,” Stone replied, “Enraptured. Exhausted.” 

“I’m sure,” he replied, “What do you need?” 

“I know we need a shower, but I don’t want one,” Stone said with a yawn.  

“You’ll feel better after,” Robotnik said, nuzzling closer.  

“I know,” Stone admitted with a sigh.  

It was true. He’d been terribly sweaty and knew he’d sleep better if he cleaned up first. He just wasn’t sure he’d be able to move, exhausted as he was.  

“Shall I go start the water?” Robotnik asked, “Or is it too soon?” 

“Would you start it?” Stone asked softly, looking up at him.  

“Of course,” he replied, giving him a parting squeezing and slipping out from under him.  

As he padded barefoot down the hall to the bathroom, the Doctor carded through his thoughts methodically. He grabbed a few extra towels and put them on the bathroom counter. He plugged in the little oil diffuser and replenished it with lavender oil and cool water, flicking it on.  

He turned on the water and closed the door on his way out, trapping in the steam. He knew Stone was likely too hot for a cup of tea. Instead, he went to the kitchen and poured a glass of sparkling mineral water over ice with a half shot of gin, then poured himself a glass of mineral water. He took a granola bar from the cabinet – the kind the Agent liked, dipped in dark chocolate. He set these items next to the towels before returning to the bedroom. 

Stone was sitting up, head bowed low between his slouched shoulders. He looked up at Robotnik with a weary, loving smile. The Doctor took his hands and tugged slightly, encouraging him up. Stone stood and followed him to the bathroom, still holding one of his hands as he trailed unsteadily behind him.   

Stone got into the shower first, sitting down on the tile floor, facing into the spray, immediately cupping his hands and pouring the collected water down his face. Robotnik stepped in behind him, setting Stone’s drink out of range of the shower spray and retrieving the soap and shampoo. He stretched his long legs out on either side of him to sit close behind him, already applying shampoo to his short hair.  

“Close your eyes,” he said, rubbing his fingers into his scalp from behind.  

Stone hummed affirmatively, feeling his shoulders relax. Once his hair was fully rinsed, Robotnik wrapped his hand loosely around his throat from behind.  

“Lean back,” he said quietly.  

With one hand, Robotnik held the glass to Stone’s lips. He shivered at the touch, gladly accepting the drink, tasting the slight bite of gin as it coursed cold down his throat. Next was soap, Robotnik’s slick hands gliding over his body, lathering him with care, letting the shower rinse it all away.  

“Tell me, was everything to your liking tonight?” he asked, hands rubbing firmly over the Agent’s muscular chest.  

“Ooh, where do I begin,” Stone said dreamily, “Everything was perfect.” 

“That’s what I like to hear,” Robotnik said, trailing his soapy hands down his sides.  

“When you left the room after? I about died,” Stone said, grinning, eyes closed as he relaxed into his hands.  

“I thought you’d like that,” he replied, “Longest thirty seconds of my week, though.” 

“When you – fuck – when you eased down onto my dick like that. I was not expecting that,” Stone said, impressed, “You just wildly surpass my expectations every. Single. Time.” 

“I aim to please,” Robotnik replied nonchalantly, but inwardly feeling a rush of relief and pride. 

“Tying that ribbon around my dick,” Stone said, followed by a little shaky moan, “The outfit, my god.” 

“If only you could’ve seen what I saw,” Robotnik said, “Bringing you to the brink over and over and over again and watching you stagger through the denial each time before begging me for more. Beautiful. Sublime. Pulling that blindfold off of you. You’re a vision.” 

Here, he wrapped his arms around Stone’s waist from behind and rested his chin on his shoulder, wanting to just hold him for a moment. He let out a soft moan when the Agent’s hand found its way up into his hair, scratching his scalp lightly.  

“You make me feel so safe,” Stone said tenderly.  

Robotnik tightened his grasp around him, hugging him harder. They stayed like that for several minutes, until Stone eased forward and turned the water off. For the next while, they sat in their towels, Stone on the closed toilet lid, Robotnik perched on the edge of the bath.  

The Agent had partially unwrapped his granola bar and was eating it slowly. They’d lapsed into an easy chat in the warm, lavender-scented bathroom.  

“Tomorrow is Saturday. Anything you’d like to do?” Robotnik asked, tightening his grip slightly on the towel draped over his own shoulders modestly.   

Stone hummed thoughtfully as he chewed, hand coming up to rub his beard in consideration.  

“Do we need anything?” he asked.  

“I could do with some very minor groceries,” Robotnik said, “Could get them anywhere in town.” 

Which, of course, meant that Stone was to choose a place to go and then they’d go to a nearby grocery store.  

“Lemme think about it,” Stone said, “Brain’s still a little scrambled. You really did a number on me.” 

The Doctor’s deep but quiet laugh made him look up at him.  

“Oh, I did a number on you?” he asked, before lapsing into a teasing imitation of his beloved assistant, “Be nasty to me. Torment me. Full boss-mode. Make me suffer. Pain is all I live for. Yes, that’s what I want. Make my life a living hell. That really does it for me.” 

It was over exaggerated, yes, but it had gotten him what he wanted. Stone had broken out into a peal of genuine laughter, waving a hand at him to stop, which, of course, he did not.  

“Oh, yeah, I love it when you’re an asshole, Doctor,” Robotnik fawned humorously, “Just be fucking mean to me until I cum. I live for it, Daddy.” 

“I do not sound like that!” Stone insisted, one arm curled around his ribs from laughter.  

Within a quarter of an hour, they were back in bed, side-by-side, hands loosely clasped between them.  

“You holding up okay?” Stone asked, “I know that was... New for you.” 

“Yes, quite okay. If I hadn’t been, I would’ve said something,” he replied honestly, “That was... Incredibly arousing, start to finish. As you would say, it was wild.”

When he recited Stone's colloquialisms, he always put an odd stress on them, signifying that it wasn't something he normally would have said. The Agent found it adorable every time.  

“If you think that one was wild, wait ‘til my next ask,” he replied suggestively.  

Robotnik laughed and let his head fall back against the headboard. Stone turned on his side, hooking his leg over Robotnik's, propping up his chin on his chest.  

“It’s going to take me at least a week to figure out a good data scheme for our experiment tonight,” he said, “Give us a little break before your next scene, hm? Some of us aren’t spry thirty-somethings, after all.” 

“I can wait,” Stone said with a chuckle, raising his chin slightly to shoot him a mischievous glance.  

“I am kidding,” the Doctor replied, “Mostly. I’m serious about logging the data.” 

“Nerd,” the Agent teased.  

“Pervert,” Robotnik shot back, rolling him seamlessly off of his chest and onto his side, curling in on him to become big spoon, “My sick little Agent. My closet deviant. Who would’ve thought?” 

"I love that you're surprised," Stone said with a grin. 

"I love that you keep surprising me," Robotnik replied, nuzzling into the crook of his neck, kissing the sensitive skin there, "You are so very interesting."

The Agent felt himself flush from the compliment, and squirm from the gentle, teasing kisses being administered to his neck. 

"Interesting enough for more experiments?" he asked hopefully. 

"As many as you like," Robotnik said, pulling away from his neck and settling into a comfortable position, holding Stone tight from behind, "I suspect, with complete certainty, that you're interesting enough to pique my curiosity indefinitely."

Stone felt a warmth spread all throughout his chest from his words. Robotnik's soothing embrace was quickly lulling him to sleep, tired as he was from the evening's exertions. Before sleep caught up with him, he spoke again, realizing he'd forgotten to say something important. 

"Thank you," he murmured, "For tonight. You're so good to me."

"It's my pleasure," Robotnik replied, voice heavy with sleep, "Anything for you."

"Anything?" Stone asked in one final act of mischief for the night. 

"Provided that proper safety protocols are in place, yes, anything," Robotnik said, clearly amused. 

Stone reached down to the arm that encircled his waist and found Robotnik's hand, joining their fingers and squeezing. The Doctor reciprocated, squeezing his hand back briefly and holding him a little tighter. 

Anything, he repeated in his mind, right on the edge of consciousness, recalling their previous conversation once again, anything at all, Agent. I trust you.