This is filth. You've been warned.
Walking through the doors, when it's the dead of night and Nardole is sleeping/recharging, is an act of surrender in itself. It shouldn't be - she is the prisoner and he her guard and rehabilitator. But this is not part of the vow.
(Except that, depending on one's interpretation, it really rather is.)
Missy feigns surprise at seeing him every time, but her little smirk tells the truth. That he is expected. That she knew he would return only hours after one of their little therapy sessions. That he is now here for something entirely different.
"Where would you have me?" she asks, fluttering her eyelids. It's a farce. She might be his prisoner but when it comes to this game, she makes the rules.
"Wherever you want," he says, locking the Vault door and turning off the containment field.
He turns around to look at her again. Her eyes are steady. Hungry. Predatory. And yet, somehow, almost warm, as well. But then, she's always been as much of a contradiction as he is.
She crooks a finger at him, and he obediently moves forward, approaching the platform where she still stands.
He can't help but glance at the chair. Usually he can't even look at it without blushing furiously; if Bill and Nardole knew the things he had done on that chair, they would never look at him the same way, and he would never be able to look them in the eyes.
Memories flash across his mind. Sitting there with a hand wrapped around his cock while he watches her lean back on the piano and touch herself, back in the early days when he hadn't trusted her enough to take down the containment field. Another time, more recently, Missy astride him, riding his fingers.
Missy smirks as he drags his eyes away from the chair and back to her. She knows exactly where his mind has gone off to.
"Not today," she says, voice gentle but firm, as always. "I want you to play for me."
"Did you have anything in mind?"
"Anything but Bartok."
He chooses Shostakovich and sits down at the piano where she has made room on the stool. He starts to play, and the music almost calms him from what he knows is about to happen.
"Good boy," she murmurs, and puts a hand on his thigh. She keeps it there, just stroking gently through the fabric of his trousers, tracing circles on the inside of his mid-thigh.
He focuses on playing and not how the simplest touch from her makes his trousers start to tighten.
"You know, I can't help thinking how nice you would look bent over this piano," Missy murmurs, lips at his ear, while her other hand strokes down his spine and makes him shiver. "Should I ask you for a couple of toys? Nice, thick toys so I can bend you over this lovely gift you got me and fuck you until you forget every name but mine?"
He swallows hard. His trousers are, all at once, unbearably tight.
"Would you like that?" she asks, softly, almost kindly.
The Doctor nods. Missy smiles, and then she's palming him through his trousers, and he's holding in a moan, and it's too much, almost.
She knows, however, when he's almost at the edge, and she stands up between him and the piano, forcing him to stop playing. She grabs his hands and uses them to push her skirts up, up and up her slender legs until he can see her suspender belt and complete lack of knickers.
She makes an 'O' face of feigned shock.
"The scandal," she says, "a lady like myself, forgetting something so fundamental, now I wonder why I would do something like-"
Her voice trails off into a shrill sound that is half a gasp and half a scream, because the Doctor has lifted her up on top of the piano and bent his head between her legs. The noise mixes with a loud, dissonant sound cluster, as her calf falls against some keys in the process.
"Oh," she says, voice high and surprised even though he's certain she isn't surprised at all. "Oh, Doctor. So eager tonight."
She's so melodramatic, making things sound so ridiculous -
"Eager for your Mistress, hmm?"
The question sends a shudder through the Doctor's body, and he pauses, leaning back just enough to look up at her. Her eyes are dark and intent, looking at him expectantly.
"Yes, Mistress," he murmurs, stroking her thigh absently with one of his fingers.
She smiles faintly, a flash of fondness in her eyes before it is replaced by desire once more. "Good. Now, back to it. Prove that mouth of yours is good for something other than lecturing."
He does as he is told, and she soon moans her appreciation, much louder than necessary, because she's a drama queen like that. He likes doing this for her, now more than ever, likes making her feel good because he knows he's the reason for so many of the tears she sheds now. (And yes, he knows that they're her fault too, for committing the crimes in the first place, but they're bothering her now because she's trying to change, for him.)
"God, I love you like this," she says, combing a hand through his hair. "It's always been my favourite thing. To get you on your knees in front of me. The self-righteous hero, on your knees in front of the one you always condemn. There's something so beautiful about it." She tilts her head thoughtfully. "Well. Beautiful and pathetic. In the best of ways."
The Doctor knows he should care more about her words. But he knows he's pathetic and hypocritical. He's known for centuries. And right now he'd rather think about the feeling of her fingers against his scalp.
"Admittedly, the piano removes some of the imagery, which is a shame," she continues, like they're discussing the weather, and his tongue isn't licking at her and making her body tremble, "but it rather provides enough imagery of its own, don't you think?"
He finds himself grinning against her. It really is an image, alright. What's even better is her completely coming undone atop the piano, and he sets out to achieve just that. Before he can, though -
"Start playing again."
He pauses for a moment, before letting his hands fall back to the keys. He sticks with something classic, soft and powerful. Moonlight Sonata's somber tune starts to fill the room as Missy pulls his head more firmly against her.
He knows this body of hers well by this point, and he's always been a quick study when it comes to sex, so it's easy enough to build her up higher and higher without quite taking her over the edge. Soon her breathing is ragged and it is likely the most arousing sound in the universe, as far as he's concerned, except for possibly the needy little noises that start escaping her after that.
"Stop teasing," she says breathlessly, "make me come, Doctor, now."
He takes a risk. He doesn't obey. He wants to tease her a little longer and is willing to suffer whatever punishment she might deal out later.
He keeps holding back just enough to keep her on the edge, and her fingers have tightened in his hair enough for it to hurt, while her mouth lets loose more demands for release. The pain at his scalp is worth it to feel her body trembling and her legs shaking against where his arms are still traversing the length of the keyboard and brushing against her from time to time.
Finally, after a lot of teasing and ignored orders, he gets her there and she comes with a soft cry. He keeps playing but doesn't take his eyes off her as she catches her breath and comes to rest her eyes on him again.
She's annoyed, now that the pleasure is fading. Her hand flexes and reaches towards him, and he flinches on instinct, in preparation.
"I should hit you for that," she says quietly, tracing the length of his face with her fingers. "I would have, before."
"I'm sorry, Mistress."
"No, you're not."
"No, I'm not," he admits, daring to smirk up at her a little. She just rolls her eyes.
"Well, I'm going to have to orchestrate some kind of payback," she says, smiling faintly at her unintentional music pun.
She glances down at his crotch, where his trousers are tented and so tight that the Doctor very belatedly realises he's in pain and has been for a fair while. Missy presses the toe of her shoe against his crotch, and he bites his tongue to stop the hiss that wants to escape.
"Sore, are we?" she asks. He nods, and she makes a face that he doesn't believe for a moment is genuinely sympathetic. "Hmm. Well, I would like to do something about that, but I do believe I'm supposed to be punishing you. I'll just have to give you a taste of your own medicine, I suppose."
He stares. Waits. Accepts his fate, whatever it might be. She's so deadly and so beautiful, he knows that he will accept far too much if it means a few more moments of getting to look at her.
Missy slides off the piano and straddles his thighs, her hands immediately going to the fastenings of his trousers and undoing them so that she can free him from his confinement. He lets out an automatic sigh of relief, and she smirks.
She strokes him for a few moments while holding his gaze, so he stares back at her and tries not to buck too shamelessly into her hand.
Finally, she lifts herself up and he's inside her, and she's all around him, and it's so good that he almost loses it then and there.
"Is that good?" Missy asks quietly, tracing his cheekbone with her fingertip.
He nods.
"Well, no matter how good it feels, no matter how good I feel - and I know how bloody good I feel - you can't come. Not unless I say so."
He'd expected as much, and thought he had been prepared for it, but he hadn't realised just how hard he was, how far gone he would be already.
Missy rocks against him as his hands grip her hips and help her move up and down. They find a rhythm, and god it's so good, the Doctor isn't sure he'll be able to last, but knows he has to. A second punishment will not be this kind.
She's leaning in closer now, so she can whisper in his ear.
"You feel so good inside me, Doctor," she murmurs, and he closes his eyes and bites back a groan. "Gonna think about this while you're gone, when I get bored and my fingers go wandering… I'll scream your name when I come. Would you like that?"
"Yes, Mistress."
"Do you want to come?"
"Yes, Mistress."
Missy smirks and rocks her hips just so, and the Doctor is so close that it takes everything he has to keep himself in control. "Say please."
"Please, Mistress."
"Make me come again first. Then I might give you permission. If you're lucky." She guides his hand so that his fingers press against her clit, and he wastes no time. Soon she's throwing her head back and moaning while she rides him, theatrical as ever.
Surprisingly, her second orgasm is quiet when it comes, and he holds her through it, so close to breaking himself that he's shaking even more than she is. She nuzzles her nose against his neck.
"Do you want to come?"
"Yes, please, I need - I need-" He can't even form full sentences anymore. He's so close and she feels so wonderful around him.
She moves her hips again, lets him thrust up into her with short, desperate movements.
"It's okay, it's okay," she murmurs, "come for me, Doctor, inside me, like I used to, inside you-"
His release comes swift and hard, and he's sure his fingers must be leaving bruises on her hips, but she's chuckling as the pleasure takes him The relief is so great that he gasps for oxygen, suddenly feeling deprived of it.
Missy kisses him, surprisingly softly. "How was that?"
He just nods and holds her tighter to him.
"Good?"
Another nod.
"Everything okay?"
The Doctor nods and kisses the line of her neck, and she lets out a contented little sigh.
"Do you need anything from me?" she asks, voice still quiet. Her eyes are intent when she looks down at him and touches his chin.
"Just you," he says, and she lets him hold her for a while, and he smiles as her hand strokes his hair gently.
Even here, even like this, he can see the change in her. She checks in afterwards, with multiple questions and far more sincerity, as opposed to a quick offhand question. Her last self, on the Valiant, never even bothered with that.
Missy eventually turns in his lap and he tucks himself back in as she gets herself settled on his thighs and lowers her hands to the keyboard. She starts talking about how much she wants to punch Bartok in the face, while playing a nice early Stravinsky piece. The Doctor shakes his head with more fondness than is sensible, and lets his hands wind around her waist, his forehead against her back.
He knows this might all end in disaster and heartbreak for them both. But for now he can hold her, and listen to her play, and hope he isn't a fool for daring to believe this might actually work.
Well, that and hope that Nardole doesn't hear any loud cries of his name coming from the Vault any time soon.
Thanks for reading, let me know what you thought!