John slipped out of the bed before Mary woke the next morning, gently disentangling himself from her limbs. He gathered up his clothes feeling strangely guilty and dressed in the bathroom as quickly and noiselessly as he could. Walking back past the bedroom, he took one last look at his wife, watching her slow breathing and the gentle curve of her bump under the duvet as she slept with one arm curled protectively around it. Then turning away, he scooped up his jacket and keys and walked out of the door without allowing himself time to hesitate.

He headed straight back to Baker Street, creeping past Mrs Hudson's door, making his feet as light as he could on the treads of the stairs; he wasn't in the mood for one of Mrs Hudson's chats this morning. He stripped his clothes off in the bathroom, turned the shower up as hot as he could bear, then scrubbed himself all over; once, twice, a third time, feeling oddly unclean. He had had sex with his wife for heaven's sake, so why did he feel like an adulterer? He turned his face up into the spray of water, letting it run over his head and his shoulders in a blistering torrent. It would be the easiest thing in the world to go back to Mary, to slip back into old routines with Sherlock, working with him, bantering with him, being his friend and his colleague. But after everything that had happened, how could he bear to return to that?

He loved Sherlock, he had no doubt of that now. He loved him with an intensity that he could never remember feeling for Mary, even in the early. Mary was comfortable and always had been. They had slipped from work colleagues, through a flirty friendship to lovers almost without noticing. It had always been easy and comforting, and after Sherlock and all that had come after, that was what John had wanted - that easy domesticity. The flat and then the house in suburbia, the cosy nights in with a takeaway and a good box set on Netflix, the nights out with other couples in a quiet restaurant, or drinks in a bar. And John had told himself that this was what he wanted - that this was real life without the cases and the craziness, and the chaos that came with Sherlock Holmes. And that has been true, hadn't it? He and Mary had been happy, truly happy. He looked over at his misty reflection in the shaving mirror over the sink and tried to work out which John Watson was the real one.

Going back to Mary would be easy. Many would say that it was the right thing to do. She would take him back without a question, he had no doubt of that. And in a few months, there would be a baby, and they would be a family and his life would be full of nappies, and bottles and baby sensory classes, and before he knew it there would be the first day at school, the nativity play, the parents evening and when he turned round he would be sixty and that would be that.

The choice should be simple; happy domesticity (admittedly with a woman who was a highly trained assassin and living under a pseudonym) or the chaos of 221b Baker Street where you were more likely to find eyeballs than a pint of drinkable milk in the fridge. But Baker Street had Sherlock Holmes and all that came with him. And John knew that he was incapable of walking away from even the hope of that.

'Fortune favours the brave.' Where has that come from? School? The army? John couldn't remember. He was a brave man, he knew that he was. And often a foolish one. And because of both those things he turned off the shower with more determination than he felt, dressed himself quickly and headed out the door to get back to the hospital and Sherlock. As he left the flat, he grabbed an apple from the pile that Mrs H has left on the fruit bowl on the table and bit into it as he ran down the stairs. It tasted sweet and full of promise, and yet somehow John couldn't help thinking of that first apple, the one that had caused all of this hassle in the first place. The one that the first woman had used to tempt the first man.

...

'Pleasant evening with Mary?' Sherlock asked as John walked into his room. He was strangely still, lying watching a daytime antiques show on the television in the corner of the room.

'How the fuck did you know that?' John exclaimed, generally amazed. He and showered, changed his clothes, he couldn't possibly smell of Mary. So how has Sherlock known that he'd spent not just the afternoon but the evening with her, and why did he feel so guilty about it? Sherlock was his friend, for God's sake, not his partner. His temper flared in its old irrational way, and the words, 'And why do you care anyway?' came out of his mouth before he could stop them.

Sherlock frowned, that single crease appearing between his eyebrows. John hoped, irrationally, that it was a sign of jealousy but when he spoke, Sherlock's voice was level and calm. With just that familiar hint of irritation and exasperation at John's stupidity.

'Oh come on, John, ' he said. 'It's hardly a difficult deduction. You left here to go and meet Mary for her scan. You were filled with wonder and awe at the sight of your unborn child. You no doubt took your wife out for lunch afterwards, united in your joy at the miracle of life. You had the seafood linguine, Mary had the lasagne. You both had coffee instead of pudding, Mary's was decaffeinated. Afterwards, you called a cab, escorted your pregnant wife home and one thing led to another. You stayed the night, woke this morning before she did, returned to Baker Street where you showered and changed, and then you came here bright and early with some misplaced sense of guilt.'

John just stared at him. 'Am I that easy to read?' he asked after several minutes of silence.

'Yes, ' came the rapid response. 'Now if you're going to get breakfast, and by the way, you look like you need the caffeine, then mine's black. With three sugars.'

John hesitated, opened his mouth to speak, caught himself, stopped, considered and then said. 'Why did you say misplaced guilt?'

'I would have thought that seemed obvious, ' Sherlock replied, and was John fooling himself or was the familiar delight in declaring a deduction missing? 'You feel guilty because you believe that you should have been here with me and not with Mary, who is after all both your wife and the mother of your unborn child. Your guilt is therefore misplaced and irrational. Your first allegiance is, and always will be - to her.'

'And you what - don't care about that?'

'Sentiment is irrational, John,' Sherlock said. Too quickly? Or was that just John's imagination again. He searched Sherlock's face for clues, wanting to run away away from this conversation but knowing that he would hate himself if he did.

'Sentiment is human, Sherlock,' John said fighting to keep his voice level. 'And I would rather have been with you.'

There, he'd said it. It was out there. 'I would rather have been with you.'

'You would rather have been exactly where you were - with your wife, and your unborn child, John,' Sherlock said, making his name sound like an insult. How did he do that? 'Which is exactly where you should have been.'

'So - what, you don't care that I spent the night with Mary?'

'I would imagine that you've spent a great number of your nights with Mary,' Sherlock said, reaching into his bedside locker for the hidden iPad. 'Why should this one be any different?'

John looked at him, mouth open, mouth closed, trying to find a retort. But Sherlock's hand were already flying over the iPad screen, typing furiously and the moment had gone.

...

Mary, it turned out, was not going to be so easy to placate.

John has turned his phone to silent as soon as he had left their house, and had steadfastly ignored it's buzzing while he kept Sherlock company that morning. As he left the hospital an hour later, realising that he was not going to get any further sense from Sherlock who was still engrossed in his iPad he finally checked the screen. Seven missed calls, twenty-one text messages. All from Mary. Shit.

He picked up the phone and called her without bothering to read them.

'What's going on, John?' She launched straight into the interrogation before the end of the first ring. She had obviously been sitting with the phone in her hand, waiting for him to call.

'Mary - I'm sorry, but -'

'Don't you dare start that, do you hear me? Don't you dare, ' she spat out her words with little attempt to conceal the anger in her voice. 'I know what comes next - 'It's too soon. It was a mistake. I don't know if I can trust you.' For fuck's sake, John Watson will you just grow a pair? I'm your wife, and you slink off before dawn without saying goodbye as if I was some kind of cheap date!'

'Mary, it wasn't like that, it's just that -' he broke off, not knowing how to explain it.

'You just decided that you'd rather be with him than with me. I get it, John.' Mary said, and the sadness in her voice was audible. 'I told you at that you didn't have to choose do you remember? And I meant it. I would never make you give up Sherlock, but he can't give you what you want, John. Can't you see that? He's not capable of it. You're never going to have a cosy little love-nest in Baker Street. It's not going to happen. But I'll wait. The baby and I will wait until you're ready to see that. And to come home to me - to us.'

And then she was gone. Just like that. And John was left staring at the home screen of his phone. To the picture of Mary, laughing as she drank champagne on their wedding day and John wondered not for the first time that week what exactly the fuck he was doing with his life.

...

He headed for the surgery, to catch up on paperwork but he couldn't concentrate, and the walls seemed to be pressing in on him. He headed out of the surgery towards the canal path and started walking, and walking, trying to get all of this confused mess straight in his head.

Because no matter how much he tried to deny it, he loved Mary, and he loved Sherlock, and he had no idea how he was going to equate the two. And Sherlock had as good as told him that it was never going to happen. And yet still, despite all of that, it did nothing to reduce the intensity of John's own feelings for him. He could spend hours watching him as he slept. Those long dark eyelashes, that perfect alabaster skin, those ridiculously high cheekbones, the Cupid's bow of his upper lip. John felt as if he could watch Sherlock sleeping for the rest of his life and beyond. And in some twisted way those last few weeks has been both the worst and the happiest of his life. All those hours, ensconced in a room with Sherlock, holding his hand, watching his chest rise and fall, feeling as if he was all that was keeping Sherlock from slipping into oblivion. He has fought for his survival, nobody had fought harder. And if you save a life don't you have a responsibility for it? Don't you have to continue to protect that person?

All those hours protecting Sherlock and he was now meant to - what - just step away? Go back to his life with Mary and the baby and work with Sherlock on cases and pretend that everything was just as it had been before?

John Watson was a soldier. He knew how to fight, and he was damned well going to fight for Sherlock Holmes.

With new resolution, he turned off the canal path towards the nearest tube station. If his time with Sherlock was going to be limited to his stay in hospital. If that was all that he was going to allow him because of his ridiculous vow to protect him and Mary and the baby as a trio then he was going to make the most of every second of it. And he was going to do everything in his power to persuade Sherlock that just for once his deductions were entirely wrong.