A/N: Prompted by anon on Tumblr.

Smut and angst together. Lovely combination. Out of all of the prompts, this was probably my absolute favourite to write.

Disclaimer: Downton Abbey isn't mine. You'll be glad of that.

Mistress

He should be strong enough to say no.

But he isn't.

She is insistent. She wants him, more than anything else in the world. She wants to know that he is hers and she is his, in some small way. She wants that piece of him in a world that seems to want them to suffer. She wants to defy everyone. She wants to be happy.

He feels as if he is losing part of himself as he utters his consent. Anna will lose part of herself – her virginity, her self-respect, her standing in society – through his own selfishness. And yet even the thought of that cannot defeat the determined look in Anna's eyes as she looks at him. Her smile should be sad, made that way by the things that she has to make do with. And yet, somehow, it is content.

He doesn't know how it can be.

Quietly, lowering his voice further so that no other punters in the pub will hear him, he gives her the directions to his dirty little room above the abandoned laundrette, slides his key across the table. Inwardly, he tries to remember if he had left it tidy that morning.

He still burns with shame when she nods, stands, and tells him that she'll see him later. She holds her head high as she leaves. No one would guess that she is about to throw away her life. John stands shakily, and returns to his job.

He doesn't concentrate at all for the rest of the day. Five times he gives out the wrong change. Three times he pours the wrong drink. Eventually, he is taken aside and told to go home, because he isn't of any use to anyone in the state that he's in. The rest of the workers eye him suspiciously. Who was the young woman? Is she the reason for his distraction? What was she doing here? They had noticed the two of them holding hands. Was she his promised? They hadn't known he was attached before. He deflects the questions easily, grabbing his coat. He won't answer them today. He needs time to think of sensible answers.

He won't get any time to think, because he is returning to his rooms. To her.

He is almost afraid of how he'll find her. Already naked in his bed? Or perhaps she has gone, changed her mind, vanished without saying goodbye.

He isn't sure which is worse.

His footsteps are loud and harsh against the floorboards outside his lodgings, and he winces. Had anyone else heard Anna's arrival? Do they know that she's here? Will they be watching, even now, with beady eyes, ready to denounce her?

He finds his room unlocked when he arrives at the right place. Guilty relief floods him. So she hasn't left. But he still doesn't know how he will find her. Cautiously, he pushes open the door.

She is sitting in the middle of his tiny living room, sans coat and hat, hands clasped in her lap. She jumps up at once when she sees him entering, a smile already fixed on her face.

"Hello," she breathes quietly.

"Hello," he replies, closing the door behind him. He takes off his hat and his coat, hanging them by the door.

"How was the rest of your shift?" she asks. "You can tell me while I make us some tea."

The statement is so homely that it makes him want to cry. It's a twisted mirror of a loving picture of contented married life. She must notice the agonised look on his face, for concern flashes across hers.

"Are you all right?" she asks.

He nods. What else can he do? What right does he have to be anything other than all right? Anna is the one who won't be by the end of the night. She shoots him a glance, but doesn't say anything more. Perhaps she knows.

It is awkward as she walks around the tiny kitchen. Unnatural. They move around in silence, a silence broken only by the clatter of cups. John knows that he should say something, but he isn't sure what. What can he give her? Empty reassurances? She deserves more than that.

"This is ridiculous," Anna says at last, and he looks up. Her eyes are fiery again. "We shouldn't be like this!"

"Well, it's an absurd situation," he tries to joke, but she doesn't reciprocate.

"It shouldn't be," she declares. "I love you, you love me, and that's all that should matter."

If only it was all that mattered.

Sighing, she puts down the kettle and walks over to him. He tenses for a brief moment before she slides her arms around his waist, nuzzling her head against his chest. His senses explode with the feel of her, the smell of her. He can't stop himself from relaxing into her touch. Anna is magical in that way.

Slowly, she pulls away from him. Her eyes are dark upon his face. He has a second to comprehend that she is about to kiss him before her lips are against his, so chaste and gentle. In all that is wrong in the world, this never could be. When they part softly, she continues to stare up at him, her gaze flickering.

"What's wrong?" he asks her.

"Take me to bed," she breathes.

The temperature of the room shoots up and freezes at the same time. The oxygen leaves the room. He has to obey.

The room that he calls a bedroom is small. Cramped. The bed is tiny. The sheets are thin and old. She deserves so much better than this.

And yet she doesn't seem to mind in the slightest. She draws him over to the bed, kisses him again, then sits down.

"Undress me," she says quietly. She is the one who doesn't know what to expect, and yet she is the one reassuring him. His heart contracts unbearably for her. He feels terrible when he realises how pathetic he's being. He needs to take control now. She might be putting on a brave front, but she needs him to let her know that everything will be fine.

His fingers set to work clumsily over the intricate buttons on her dress. His mouth moves gently to the shell of her ear, sucking it lightly into his mouth. Her breath is fluttery against his face. Her hands tremble as they move to start undressing him, too.

He sees the first bit of nervousness when he lays her bare against the sheets. Her limbs are tense, hands pressed sharply against the covers. He can tell that she is resisting the urge to cover herself. She doesn't need to. Her body is breath-taking. Miles of milky skin, shapely and slim. Small, pert breasts, dusky pink nipples. Blonde fuzz drizzled between her legs.

She is more beautiful than he ever could have imagined. He tells her so hoarsely, eyes riveted to her. He sees her relax just slightly, and he leans over her to kiss her. Her lips are soft and yielding. She has given complete power over to him, trusting him to show her what to do.

He shifts so that he is on his side against her. He encourages her to turn to face him, propping himself on one elbow as he gently rests his hand behind her head. He kisses her slowly, languidly. He won't rush even one second of this. It might not be their wedding night, and it might not be right in the eyes of society, but he intends to make it as right as he possibly can. He needs her to be comfortable.

She inhales sharply when the palm of his hand comes up to brush against her nipple. He shushes her gently, kissing her temple, continuing to explore, rubbing his thumb around the rim, feeling it change beneath his fingertips. He bends in to kiss it gently, sucking it into his mouth and rolling it between his teeth, his fingers repeating the process over her second nipple. Now her fingers are curling through his hair, and she is breathing more heavily, her body tensing. He can see a flush of pink staining her flesh. Slowly, he slips lower, his mouth caressing the planes of her ribs and her waist and her stomach, before coming to a rest just above her hairline. He hears the nervous hitch of her breath, her fingers trembling more pronouncedly against his hair. Gently, he parts her thighs, letting her get used to his fingers resting close to her, giving her the opportunity to stop him if she so wishes.

She doesn't.

He strokes his fingers closer to her centre. His ministrations to her breasts have left her damp, and he slowly touches just one finger to her. She whimpers and jerks, and he waits until she's settled before moving again.

"Is this all right?" he breathes.

He lifts his eyes to find her nodding. He unwinds one of her hands from his hair and brings it to his lips, kissing it gently in reassurance.

"Trust me," he says softly.

"I do," she replies inaudibly. The statement shatters and heals his heart in one breath. He does not deserve her trust.

But he is determined to try his best to be worthy of it.

Slowly, he returns his fingers to the apex of her thighs, tenderly running his fingers along her. Her gasp is sharp, but this time he doesn't stop. He simply continues onwards, his touch feather-light, feeling her ripple against him until – success – she begins to rock her hips in time with his fingers. He shifts back up her body, kissing her mouth gently, looking deep into her eyes.

"Does that feel nice?" he asks her softly.

Her nod is shaky, her thighs widening of their own accord. He takes it as his invitation to finally breach her folds with his fingers.

She's hot and she's wet, and it's a beautiful combination. He kisses her more fiercely, his thumb rotating to find the sweet bundle of nerves that will eventually prove to be her undoing, and she cries out inadvertently when he finds it. He removes his lips to her ear, softly telling her that he loves her, that he's the luckiest man alive, that he's never known a more beautiful woman to exist. She pushes her forehead desperately against him, clinging to him tightly as the feelings begin to well up and take over, and he keeps going, feeling the way that she grows slicker by the second, reading the progression of her climb to completion in her eyes.

When it finally takes her – mewls soft, back arching – he kisses her gently, holding her close to him as she recovers. It takes less time than he had expected for her to look back up into his eyes and nod.

She is ready. For him to take her, to make her his mistress.

He shakes with as much fear as desire as he slowly shifts himself until he is hovering over her. She touches his face.

"I love you," she breathes, voice wavering just slightly.

"I love you too," he echoes, the pad of his thumb brushing just beneath her eye. She widens her thighs for him. He slips between them. He links the fingers of his right hand with her left – the hand that should be sporting his ring – holding on tightly, needing to reassure her in some way.

Or perhaps it is him who needs the reassurance.

He latches the fingers of his spare hand to the nub at the top of her sex, beginning to rub just softly. She moans quietly, her head rolling back, and he slowly begins to push himself into her.

There is discomfort, he knows there is. It's in the way that she scrunches her forehead and bites her lip, her eyes squeezed tightly closed, and he hates himself more than he ever has done before in that moment. He is hurting her.

But then she opens her eyes and stares at him.

"It's all right," she says. Her voice is quavering, but he can sense the steely determination behind her words. "You can carry on now."

She feels incredible, he can't deny it. She is so tight and hot. She is better than he has ever dreamed (oh, how he has dreamed), and he shifts his hips just slightly. The sensation that shoots through his entire body is more intense than he had been anticipating, and he can't stop himself from shuddering and grunting. It has been so long since he had last touched a woman like this. He has almost forgotten the complete gratification that swells up in his entire body.

But he won't allow himself to get too carried away. Anna needs him to be slow and gentle. So he will be.

She squeezes his hand tightly as he rocks within her. He can tell that she is still in pain, though she is trying not to show it. He massages her gently with the fingers on his other hand, rubbing the nub gently, trying to make her feel as good as possible. He feels the almost imperceptible rise of her hips, and moves to kiss her. She responds gently, her spare arm moving to the back of his neck, holding her to him. He doesn't stop kissing her for even a moment, letting his lips caress as his fingers massage. And even though it probably still hurts, he feels the tension in her body – the tension that he is learning is Anna's way of letting him know that she is close to the end. He redoubles the efforts of his fingers, feeling his own climax fast approaching – the friction of her around him as he moves within her is just too much – and she shudders lightly in his arms, groaning aloud. The sound of her satisfaction triggers his own end, and he pulls out jerkily, showering her stomach in thick strings of his pleasure. She jerks in surprise at the sensation, and for an instant he is ashamed. But he won't risk ruining her forever by getting her pregnant.

"I'm sorry," he apologises, but she shushes him, telling him that it's all fine.

He leaves her for a few moments to retrieve something to clean them both up a bit. She winces at the sight of her blood pooling on the sheets – she hadn't realised that there would be quite as much – but he kisses her gently and tugs it from underneath her. He knows he should try and remove the stain now while it is still fresh, but he doesn't have the heart to leave her there, shivering and naked and alone in a foreign bed that isn't truly his, either. He retrieves another sheet from his tiny linen cupboard, kindly donated to him by his landlady, and encourages her to sit up while he remakes the bed. Once he is finished, she slides beneath the covers and he follows her, taking her up in his arms. She is sweating, and she nestles herself close to him, her ear over his heart. He kisses her hair and wraps his arm tight around her, entwining their fingers again. For the time being, they can lay just like this, forgetting about the outside world.

Until he has to ask the dreaded question.

"What time do you need to leave?" he asks her quietly. "When's the last bus back to Downton? I don't want you getting into trouble."

"I can stay the night," she says sleepily. "I told Mrs. Hughes this morning that I was going to visit my sister. And I telephoned her earlier and told her that my sister was ill, and that I needed to stay home for the night. She said she understood. As long as I'm back for dressing the girls in the morning, I'll be all right."

His heart swells in his chest. She can stay with him for the night. He can hold her naked in his arms and relish the feel of her skin. And, just for a moment, it doesn't feel quite as sordid, quite as dirty. She is not casting herself from his room like a lady of the night who is not being paid for her services. She is staying in his bed, just like a wife.

This whole situation is wrong. John knows it. He knows it will haunt him in the future. But, just for tonight, he can't stop himself from being happy. He has Anna with him. They have made love, pledged their bodies to each other even if they can't pledge their names.

For tonight, it is all enough.