John wondered when he had somehow become such a fixture in 221B that even Mycroft took his existence there for granted. He could think of no other reason that his return to the flat would be so unremarkable that the Holmes brothers would be unaware of his physical presence. Although, they did seem quite engrossed in flinging scathing comments and cutting remarks back and forth, sniping at one another with just the merest twitch of an eyebrow or tilt of the head. But still, he'd never before found them so oblivious to their surroundings that anyone might walk into the room unnoticed. Even him.
He shook his head slightly as he leaned against the door frame, watching the non-verbal sparring match in front of him.
He saw a twitch in Mycroft's jaw and started. It was a twitch John only ever saw on the man's face when he was talking with John. Or, perhaps, about him?
John turned his attention to Sherlock. His friend's face wore a fixed scowl, but that was normal when he was dealing with his brother. There was a look about his eyes, though, that suggested worry. John had seen rather a lot of that odd tenseness around Sherlock's eyes in the weeks after his return, when he'd been unsure of his welcome. They had danced around each other for months, with that tightening of his expression returning with every misstep. Eventually they had settled into their new reality, and Sherlock's expression had relaxed. It had been more than a year since he'd seen that tenseness around Sherlock's eyes. John was not pleased to see it return.
The silent exchange he was witnessing was about him, he realized. Mycroft was talking about him, and Sherlock was worried. John rolled that thought around for a moment and snorted to himself.
"That's not something you have to worry about, Mycroft," John said from the door way, taking a moderately obscene amount of pleasure in watching the brothers turn to him in surprise. They rose from their seats as he pushed himself upright and moved into the kitchen to put the kettle on. "Tea?"
"Thank you, Doctor Watson, but no. I only stopped by to ..."
"To stick your nose in my business."
John watched as Mycroft's eyebrows rose. The man was clearly flummoxed by John's interruption. He was more than used to that sort of thing from Sherlock, but it was unexpected coming from John. A glance over at Sherlock revealed a similarly shocked expression. Sherlock caught the glance and tilted his head a fraction, considering. John smiled, watching the mad genius try to work it out.
Chuckling, he turned his back on the Holmes brothers, switched on the kettle and pulled two mugs out of the cupboard. He heard Mycroft take a breath to speak and cut him off without turning.
"I understand your motivation, Mycroft, and I appreciate it. Really, I do. It is, however, none of your business."
"John," Mycroft began.
John's lips twitched in amusement. First names now?
"I can spell it out, if your observational skills have failed you, but really," he said, turning back to lock eyes with Mycroft, smiling broadly, his gaze calm and serious, "it's not something you need to worry about."
John heard a soft intake of breath, but didn't look over to Sherlock. After a moment he saw a flash of something like relief flit across Mycroft's face, and something else as well. Something he wasn't sure he'd ever seen there before. He'd seen the pompous git look supremely satisfied, and this was something akin to that, but without the usual insufferable smugness. If he hadn't known Mycroft's opinions on 'sentiment,' John would have sworn it was happiness.
John's smile widened. Mycroft inclined his head.
"Yes, well. I'll just be on my way, then. Good afternoon, John. Sherlock."
John listened to the stairs creak as he turned his attention back to the kettle, quickly fixing two cups of tea. He rotated the handle of Sherlock's mug and was unsurprised to see the man's pale hand reach out to take it, though there had been no sound of him crossing the room.
They stood in silence for a moment, sipping their tea. John turned to look at his friend when he felt Sherlock's weight shifting.
"That was amazing."
"That's my line."
"John. How did you …?"
"I've been watching you do it for years. Was bound to pick up a thing or two," John replied with a smile, then tilted his head. "You don't have to worry about it, either, you know."
"Who said I was worried?"
"You did."
John watched Sherlock consider denying it and discard the idea.
"I can't help it. Someone will come ..."
"Sherlock."
"John. Someone will come ..."
"Someone already has."
John watched Sherlock stiffen, the tightness returning to his eyes.
"And you have nothing to worry about."
He watched as Sherlock's eyes flicked up and down, reading him. Deducing him. He saw realisation light up those remarkable eyes as they came up to meet his.
"So, you're not going to ..."
"Idiot," John breathed, bringing his tea up to hide his smile.