Warning: Sexual content. 18+ only.

It was an honest mistake. Wasn't that how these things always started? You thought it was safe to look through his private book collection. Surely he kept the dangerous books in his private laboratory, not on the shelves in your home library. Wrong. It could have been worse, all told. You might have discovered a book that spay poison, or one detailing gruesome dissections.

Instead, the book had left you red-faced, kneeling on the library floor, mind riddled with filthy fantasies.

Who knew Mayuri had run so many sex experiments? Or had created so many…inventions. You flipped through the pages, poring over each brilliantly-drawn device. They were rendered in excruciating detail. Every button and nodule labelled. Every…protrusion. Your tongue darted out to wet your dry lips. Mayuri, Mayuri, Mayuri. The small blocks of text on each page made your heart pound. Mayuri had written these words. Mayuri had thought of these things.

Who knew he had it in him?

When Mayuri finally dragged himself home from the lab, you were going to have a little chat.

Fools. All of them, bumbling, hamfisted idiots with pork dumplings for brains. If Akon hadn't vowed to clear up the mess and discipline those involved, Mayuri would have levelled the entire laboratory with a the small incendiaries he'd placed everywhere. Not even Nemu knew about those. Originally a failsafe measure for outright disaster, he'd taken to thinking of them every time one of his subordinates ticked him off.

It was probably a sign he needed to go home. The best way to curtail murderous tendencies was a hot shower and short, deep sleep. Perhaps he would even sit with _ for a while. She was blessedly quiet most of the time, and it would soothe his nerves not to be surrounded by incompetence.

Mayuri left the laboratories with a vein throbbing in his temple (he should really just remove that) and a cool rage still lurking beneath the surface. He would calm himself with some light experimentation at home. His personal lab was free of subordinates and stray, careless fingers. And there was that fascinating theory on Hollowfication he'd been tinkering with for half an age.

His own quarters were but a short walk from the labs. Before, he'd simply had a room within the laboratories themselves, but his acquisition of a partner had required some changes. Even he could see the good sense in having a space apart, since when he was at work he could focus entirely, without intrusions from his personal life. And _ appreciated not having to live in the midst of a thousand experiments.

He removed his white haori in the hall and proceeded straight to the bathroom to disrobe and clean away his make-up. There would be no returning to the laboratory tonight. His mind was in no state for it. As much as the thought disgusted him, he was distracted. Abominable.

The house was curiously quiet, he mused, turning on the shower. The spray hissed, splattering against the tile. Perhaps she wasn't home, though he was at a loss for where she would go. He knew, dimly, that she had friends with females from the other divisions. It had never occurred to him to wonder who, or care much.

She was good like that, he thought, stepping into the spray. She would amuse herself and not pester him overmuch. She had an inquisitive mind, but enjoyed seeking answers on her own. The water hit his naked back. He turned his face into it, allowing the thick black and white paint to smear and run down his neck and chest. It was what had caused him to notice her in the first place. Why on earth was someone in the eighth division requesting copies of his publicised research from the archives? He'd traced the activity, learned her name, and learned to watch her.

Finally, he'd found himself confronted by a quiet young woman, asking if he'd made any further progress into the development of an obscure strain of virus research, because she'd read all of his research and it had ended abruptly. Mayuri recalled that research. He'd dropped it as soon as something more interesting came along. When he told her as much, she had looked disappointed for half a second, before demanding to know what was so interesting he'd had to switch. From there, she'd squirrelled her way into his life, his house, his bed.

He leaned his head back, blinking water out of his eyes. Perhaps there was a source of distraction, if he chose to take it up. Then, as if the universe had been reading his mind (perish the thought), her voice cut through the shower spray.

'Mayuri, could I talk with you about something when you're done?' Her voice, though quiet as ever and half-muffled by the water, had a strange edge to it. He looked round. She had something tucked under her arm. His golden eyes narrowed. It looked suspiciously like one of his research books. Ah, so she wished to discuss one of his old projects. Well, no harm there. She was a good sounding board for ideas, attentive, quiet, inquisitive. It might have been the heat from the shower, but her face was oddly flushed.

'Fine,' he conceded, unconcerned at his own nudity. 'Just get that book out of here before the damp gets to it.'

She nodded, turning and leaving without any further behest. Mayuri closed his eyes and ducked beneath the water, intending to enjoy the rest of his shower in peace. The last he would know for a while.

You drummed an impatient tempo on the cover of the research book, eyes fixed on the library door. Your insides were squirming with anticipation, overlaid by a slight, icy nervousness. If he told you to get out and leave him alone you'd be bored and distracted all night, thinking of what might have been. But, if he was in the right space between boredom and indulgence, he might give in to your request. Run a little experiment on me, Mayuri. Just a little one. Perhaps not. If you phrased it like that, he might think you wanted an extra arm or something.

Footsteps in the hall. He appeared in the library doorway, a grey yukata looking strange against his (for once) human-coloured skin. His royal blue hair was shoved away from his face, tousled and still-damp after towelling off. He gave you one glance, then looked at the shelves to see what the missing volume was.

His gaze snapped back to you. 'You stumbled across that, did you? Too disturbing for you, was it?' If you weren't mistaken, there was a mild hesitation in his words, as though he was embarrassed. 'Give it here.'

You pressed your lips together and held the book tighter. 'What did you do with them?'

Mayuri's eyes narrowed. 'What?'

'The devices you made? Where did they go?'

'Why would you want to know that?' he asked, suspicious. 'What a stupid question.'

You flipped open the book to the one picture that had captivated your mind all afternoon. It was done in lurid detail. You tapped a finger against it. 'I'm particularly interested to know what happened to this one, Mayuri-sama.'

He stared. '_, what is wrong with you?' He stormed over, taking firm hold of your wrist. 'Did you ingest something in my laboratory, you foolish woman?'

Amusement warred with irritation. You got to your feet, pressing your free hand against his cheek, ignoring his expression of outrage. 'I haven't touched anything in your lab, Mayuri. But I do want to know about these marvellous creations of yours. I've been thinking about them all day. Your research is so very detailed, but I'd like to see them, to experience them, in person.'

He looked as though he'd been struck over the head with a glass beaker. He released your wrist of a sudden, staring at you in disbelief. 'What is this?'

You smiled, giving a little shrug. 'You see everyone and everything as something to be investigated. Why not investigate me, with these? You flipped through the pages, shivers running down your spine at some of the illustrations. 'You stopped because you couldn't find the right test subject, correct?'

'That research was a waste of time.'

'But,' you countered, 'why let all of those inventions go to waste? You're home early and you've bathed. You have nothing else planned for the evening.'

'Foolishness,' he muttered, jerking the book out of your hands. He ran his one overlong fingernail down the page you'd been staring at, eyes flashing like gold coins as they darted up to look at you. 'I'd no idea you were such a degenerate.'

You touched his upper arm. 'Everyone has their facets. Why not discover some more of mine?'

He snagged your chin in his right hand, that long fingernail tapping your cheek. He stared at you, cool and calculating, for what felt like an age. When he let go, you were ready to be disappointed. Mayuri's moods were fickle as Spring winds- He took the book and tucked it under his arm, then took hold of your elbow. As he steered you from the library, your heart began to pound.

'You will do precisely as you are told,' he ordered. 'Obviously, I will not allow any damage to occur to you, but if you are going to help with my research, you will obey my commands, and answer questions when they are given.' His voice had a rough undertone that sent chills through you. His lab was in a separate part of the house, beyond biohazard doors he accessed through his elaborate security protocols. The lab was comparatively small, but well-equipped for his private experiments. He led you over to a flat, padded table. There were straps and…stirrups. 'Strip and lie down.'

'Mayuri…' you started, caught half between lust and trepidation. 'You don't need to tie me.

'If previous experiments taught me anything, _, it is that you will need to be restrained. Lie down.'

You swallowed your nerves, undressed, and lay down. Mayuri strapped down your wrists, your elbows, your hips, and after placing your ankles in the stirrups, spreading your knees wide open, he tied those too. Your face flamed red, even as the cool, sterile air of the lab brushed over your skin, raising goosebumps. You were completely vulnerable, lewdly exposed, and damn if you weren't enjoying it. Mayuri reappeared with a handful of EKG leads. He smoothed your hair out of the way, sticking one against each temple. Moving down, he attached more to your chest to measure your heart-rate and breathing. If he noticed your laboured breathing, he made no comment.

'Wait here.' As though you could do anything but. He left your immediate line of sight to begin rooting around in the storage cupboards. You turned your head, trailing EKG leads, to watch him. He took his white lab coat from the stand and drew it on. 'I knew I left it around here somewhere.'

He straightened up with a heavy white box. Grunting a little beneath its weight, he carried it over to the examination table, placing it on the side-counter. It required a drop of his own blood to open, which he gave. He didn't want anyone else to stumble across it, you realised. But why was the book in the library? The contents of the case drove all thoughts from your mind.

Lovingly nestled in their own little compartments, were a selection of bottles and…toys. Your eyes widened at the sight, and damp heat pooled between your open legs. He was going to use those on you. Mayuri saw your expression, and huffed, amused. He picked up an unmarked silver bottle and leaned over you.

'I had no idea you were so depraved, _.'

'You're the one who invented all this,' you challenged, gasping when something cold dripped onto your bare left breast. The gasp turned into a sigh as his gloved fingers -when had he even put those on?- rubbed the cool gel into your nipple, which immediately began to tingle intensely. 'W-what is that?'

'A stimulant,' he said blandly. 'It will make your nerve endings precisely five times more receptive than usual. Any more than that, and I'd end up with you foaming and drooling all over my lab.'

'Mayuri.' He was already applying the stimulant to your other breast, leaving the first slippery and hard as a diamond.

'Cease your prattling.'

'Mayuri-sama,' you breathed, toes flexing and curling when he moved to stand between your legs. You could already feel your nerves pulsing, reacting to just the air. If he applied it there… Cool, viscous gel dripped. Your entire body seemed to tighten, even before he rubbed it in. A wordless moan left your lips, and you arched against the restraints. He coated his fingers and slipped them inside you, twisting them to spread the stimulant as far and evenly as possible. 'M-Mayuri!' His name grated out of your throat.

He slipped his fingers free and watched you with cool dispassion. The slight breeze from the air-regulator felt like a thousand electric kisses over your erogenous zones. You were going to come from this alone, tied down and spread wide, while he just stood there and watched you. He pulled off his latex gloves with a snap, threw them into a hazardous waste bin, and put on a clean pair.

He deliberated far too long over his little collection for it to be just indecision. He was tormenting you. Or at least, that was how it felt. By the time he turned around, your hips were bucking, your body burning. Small, shamefully needy whimpers left your throat. He had it in his hands - the device you'd been staring at all day. Your stomach gave a lurch.

It was a vibrator, but more complex and intuitive than a vibrator could ever be. A clean shade of white, it was phallic with a heavy base that would attach to a mechanical arm at the base of the examination table. The length that would fit inside you was larger than anything you were used to, close to seven and a half inches, riddled with vibrating nodules that stimulate the walls of the test subject's vagina. The phallus oscillates in repeating patterns to provide further stimulation, in accompaniment to the clitoral attachment. See fig. B for-

Your mind jerked away from its remembrance of Mayuri's notes when he lined the tip of the vibrator up with your entrance. Even that small nudge sent starbursts of pleasure through your nerves. He wasn't finished, not by far. There were more secrets in his box of tricks. He smiled, a little sinister, as he brought out two small, round objects. They were flattish, and white. You hadn't seen those in the book.

'W-what are those?' you asked, breathless.

'They adhere to your breasts,' he said with clinical detachment. 'The gel activates the motion.'

Motion? What motion?! You found out soon enough. The second the first disc touched your gel-covered nipple, it contracted around it, pulsing rhythmically. It was sucking. Your fingers clawed at the edges of the table, head tilting back. Shit. The feeling was intense, and only doubled when he applied the second. Sweat began to form on your forehead. He'd barely begun and already your thighs were quivering, your heart thundering. What the hell had you let yourself in for?

He returned to the vibrator. Your mouth fell open as he guided it inside you. It wasn't switched on yet, but the nodes and bumps running along the length caressed you like nothing you'd ever felt before. It was a stretch, its girth widening the further inside it slid.

'Relax, girl.'

His voice only made you shiver all the more. His instruction was impossible to obey. When the device was seated fully inside, he repositioned the attachment, a round disc identical to the ones on your breasts, and pressed down. Your eyes flew open as it sealed itself around your clit and began to suck. A moan left you. You were going to come right there and then.

He flipped a switch at the base of the vibrator. It whirred into life. Your restraints must have been made of something extra strong, because you jerked and thrashed at them like a woman possessed. Mayuri stood back, picking up the EKG reader, but he barely glanced at it. His eyes were fixed on your body, as you arched up, again and again.

You were going to shatter apart into a thousand pieces. The gel had turned your ordinary nerves into minature supernovas, setting them off with every buzzing, rubbing jerk of the vibrator. All while your oversensitive clit and nipples were sucked with blind, inhuman hunger. Your mouth was open, eyes closed, moans and gasps and grunts spilling out.

The pleasure build into something so intense it locked every muscle of your body so tight you half wondered if your bones would break. You didn't know how long it lasted, but it seemed an age that you were stiff and shuddering with pleasure, almost seizing up with it. You ripped through the first layer of the padded table, fingers curling into the fabric, needing to hold onto anything.

It was near painful. Kicking, bucking, striving to get away from the merciless machine and the relentless suckling of your most sensitive areas, you were helpless, tied down and pleasured and watched by your scientist-cum-torturer. There was no escape.

'May-M-Mayuri…' you gasped, tears leaking from the corners of your eyes. He leaned over you, pretending to be tapping the EKG leads, making sure they were still in place. He gave your splayed, shaking body a look of satisfaction, and offered you a faint smile.

'You were just the distraction I needed,' he said, as if in praise. 'Your results will be very useful, _. I believe I'll have to try everything on you.'

When your body was locked up in an agony of pleasure, stimulation, and desperation, there came an extra nudge from the vibrator that sent you screaming over the edge. You kicked so hard your leg flew out of one of the stirrups. You were blind, deaf, dumb, to everything but the explosions going on behind your eyelids, and your nerves were so overburned they might never feel anything again after he was through with you.

Mayuri moved around you as you fell back to the examination table, slick with sweat, your thighs coated in your own fluids, your limbs weak and twitching. He eased the vibrator out. You groaned as its retreat set off faint sparks and ripples. The discs detached with a touch from their creator. You shuddered with relief.

'Not a bad experiment, though I see I'll have to use stronger restraints,' he said. He took a towel from one of the cupboards and began to wipe off the table, and you, since you were in no fit state to move. You groaned when he brushed over the areas the gel had been applied. 'Stop complaining. That will wear off within a few hours. You were very receptive to the gel and the instruments.' He stopped to check the EKG. 'More so than previous subjects. That was only level one out of fifteen.'

Your head jerked up. 'What.'

Mayuri turned the screen so you could see. Your heartrate and brainwaves were off the charts. He tapped the screen with his fingernail.

'Keep your evenings free. We have a lot of work to do.'