John and Mycroft are in a yellow-wallpapered parlour with French windows opening onto a rose garden. Mycroft appears fresh and serene as always. No bags with him. He has simply appeared in this location, and is now standing by the French doors, looking out at the roses. John shut the hall door behind him as he entered, hoping to hide any noise Sherlock might be making.

John is standing awkwardly in the centre of a rug worked with a floral pattern. Like the rest of the house, this room is cosy and calm.

John has tried to ask a couple of questions about the weather, to initiate a harmless conversation, but Mycroft has been monosyllabic. John wonders how much time Sherlock needs.

Mycroft turns back to face John and speaks. "You sleep with him." Tone of absolute certainty.

How does Mycroft know?

"Your bedroom light fails to go on, on a very regular basis," says Mycroft disdainfully, as if he has read John's mind.

It means nothing, is a taunt. John doesn't always put the light on if he's heading straight to bed - what would be the point? And yet, on two nights at least, it is literally true that he slept with Sherlock.

But John is in no mood to discuss his private life with anyone, least of all this overtly hostile man in a suit which probably cost more than cars John has owned but which John still finds repellent. So he thinks John and Sherlock are having sex. So be it. He will not dignify Mycroft's accusation with an answer.

"Your life choices are your own, of course -"

"Yes, thanks, they are."

"- However my brother has a brilliant but fragile mind. He must not be allowed to descend into the mundanities of a lifestyle -" Mycroft is spitting - "which revolves around daytime television and the pursuit of pointless social activities."

He pauses, looks John up and down. "When I first met you I was impressed. I saw you as someone who could support Sherlock without too much interference. Your own personality was so weak as to be subsumed by his, as was only natural."

John's nostrils flare, but otherwise he is motionless.

"But as time moved on it became clear that your presence was placing Sherlock under unreasonable strain. The madness with the apparent suicide. Because of you." John's eyes widen in amazement. "The time wasted in laddish capers and on enforced familial contact on your part. Because of you. I realised that he was in danger. Although my brother is incapable of forming attachments in the conventional sense, you are clearly important to him, on some level. That importance means that he has an Achilles heel which will always be available to his enemies."

"You're saying you want me to leave because I place him in danger? And because Sherlock and I sometimes sit in front of the box drinking beer?"

"In essence." Mycroft looks pleased with John's quick grasp of the principal points.

"Well, now you put it like that, it makes perfect sense. I don't know why you didn't just ask me in the first place." John's tone is light and careless, a tone which Sherlock would recognise but Mycroft does not.

Mycroft starts to reply but John cuts him off.

"Shut up. Not a word from you. You don't know anything about the life he and I lead together. You have no idea about friendship or love or how we are better together."

"Very poetic," says Mycroft, "but it risks Sherlock's life every day. "

"No," says John. "He risks his life every day, and that's his choice. He chose me as his ... He chose me," he goes on, stumbling a little, "and that is nobody's business but his and mine."

"So you won't go, then?"

"What are you offering if I do?" John plants his feet apart, folds his arms and waits.

"No more surveillance." Mycroft glances towards the closed door. "He will return to his proper state, with my full support, which as you know is not inconsiderable."

John pauses. "You will leave him - alone?"

He speaks with absolutely neutral inflection.

"Yes," says Mycroft, not seeming to notice. "If you promise you will do the same."

John moistens his lips, shifts on his feet and then returns to his previous steady stance.

Mycroft nods at him. "Will you promise me that you will not try to finagle him into some kind of romantic domestic situation which will cripple his abilities and endanger the security of the very nation?"

John looks at him for a long time. Mycroft waits with an increasing air of victory.

At last John speaks. "No. I will not promise that."

Mycroft's eyebrows shoot up. "You would risk his sanity, already at cracking point, for this so called love?"

"I don't believe he is any less sane than I am. He is certainly saner than you. In my medical opinion. So yes." John's chin is up.

"Very well. On your head be it."

"I'm very happy with my actions and responsibilities towards Sherlock," says John. "Are you?"

He turns and walks away. Pulls open the door with barely contained anger. Almost walks right into Sherlock, standing outside the door obviously listening.

"Let's go," says John, taking in with a glance Sherlock's set jaw and deadly eyes. "We don't need to waste any more energy here."

Sherlock is looking at Mycroft with a terrible coldness. He opens his lips to speak.

"You are not him," says John. "You are a human being."

Sherlock closes his mouth. He rests his hand on John's shoulder - John feels the tremor of fury in his fingers - and nods once. John leads the way out of the house and into the bright August afternoon.

Author's Note: Yes folks, it's Mycroft as Lady Catherine de Bourgh, inviting John to deny Sherlock. I simply could not resist.