"What's he looking at?" John asks, managing to sound both vaguely curious and vaguely disinterested at the same time.
Sherlock's eyes snap back to John.
" I mean, who wouldn't want to-"
"He's coming over." John gestures with his can of Fanta before taking a sip.
Sherlock leans down further over his half eaten cafe breakfast.
"Yes." Sherlock only spares a glance sideways, not bothering to meet the man's eyes.
The man holds out a small package. "For your brother."
"My-" Sherlock grabs the small box.
The man just walks away.
"Hey! That's Mycroft's!"
Sherlock rips the paper off anyway to reveal a small black box with a card on top.
"You can't just-"
"Expensive. Blond Street. Store's own stationary." Sherlock holds the card up to the light. "Fountain pen. Probably written by shop assistant."
John sighs and takes the opportunity to steal one of the mushrooms off Sherlock's plate.
Sherlock sniffs the card and frowns.
"What?" John is reaching for a second mushroom with his fork.
"Someone's deliberately sprayed aftershave on this."
"People don't do that anymore."
"No?" John shrugs and goes for a chip instead. "Maybe Mycroft likes it."
"Why does that matter- you can have that tomato as well." Sherlock doesn't take his eyes from the card, turning it over in his hands.
"What does it say?"
"The card?" John helps himself to the neglected tomato on Sherlock's plate.
"Nothing." Abruptly Sherlock thrusts both card and box into a pocket and goes back to eating breakfast.
When they get back to the flat John barely has time to take his jacket off before box and card are shoved under his nose. The box it turns out contains a pair of cufflinks and the card a quote from a poem:
The Grave's a fine and private place,
But none I think do there embrace.
"To His Coy Mistress." Sherlock snaps in irritation.
"Yes, I know that."
"Someone is propositioning my brother." Sherlock's fury is self-evident.
John starts to laugh.
"I don't see how that's amusing."
"You, you're jealous."
Something in Sherlock's tone causes John to sober. "You really aren't, are you."
"I'm going to find whoever's responsible for this" He points angrily at the box and card that John's still holding. "And kill them."
Two days later Mycroft arrives for an apparently casual visit. He doesn't bring manila folders with him or give orders or even enquire pointedly about what Sherlock's been doing. Instead he sits comfortably in the chair he usually occupies on his visits, sips tea and talks genially about the weather to pass the time. John doesn't know what to say to that or the fact that Mycroft seems to be content to wait for Sherlock to come back.
When Sherlock does return his usual whirlwind of energy seems to die down at the sight of Mycroft.
Mycroft sips his tea and then begins conversationally: "That wasn't very nice of you."
"It had to be done."
"Still, it was rather an alarming response all things considered."
"I've made my point."
"Yes, I suppose you have." Mycroft leans back to look up at Sherlock who now stands over him.
Mycroft smiles his politely malicious smile.
In an instant Sherlock is bending over him, hands braced on the arms of the chair, face all of two inches from Mycroft's. "If he ever lays a hand on you I will kill him." He bites out.
Mycroft doesn't react beyond holding his teacup out to the side for John to take from him. "You should probably go out. My brother and I have something to discuss."
"Mycroft, are you listening to me?" Sherlock snaps to the sideways slide of Mycroft's gaze rather than his words.
"Yes, I am. I always do." Then as if to pacify Sherlock he reaches up to cup his face with both hands.
John sets Mycroft's tea down and all but runs to the door to get out of the flat before anything else can happen. He makes the mistake of looking back as he reaches for his coat. Sherlock has a knee resting on the seat, between Mycroft's legs and their faces are so close that John doesn't want to believe what he's seeing. He leaves in a hurry, pulling the flat door and then the downstairs door abruptly shut behind him.
When he returns to the flat, over four hours of ceaseless walking later, it's with the conclusion that he was right. Sherlock is jealous, just not in the way that John first presumed. Which would be fair enough if only it was about attention, about Sherlock both wanting and hating the fact that he was as near enough the centre of Mycroft's universe. That would have made sense. The spoilt little brother wanting all eyes on him. Maybe that's even all there is to it, John tells himself, maybe they're just strangely physically familiar with each other, maybe all Mycroft was doing was reassuring Sherlock that all eyes were indeed fixed on him. Maybe John hadn't just seen what looked like a kiss. After all, it had only been a quick glance.
Having talked himself into his conclusion John is in a much calmer mood when he walks back into the living room, expecting Mycroft to already be gone. Curiously, Mycroft is still there, on his feet at least, adjusting his tie and fussing with his shirt cuffs as if he's expecting them to be in disarray. All of which has a perfectly sensible explanation John's sure. What has less of a sensible explanation is Sherlock sprawled back against the couch, running a finger over clearly reddened and slightly swollen lips and looking smug about it.
"John." Mycroft greets him as if there's nothing particularly amiss about the situation.
"I... didn't think..."
"Our discussion took longer that I'd expected. So kind of you to give us the space."
John nods mutely to that.
As Mycroft passes John at the doorway he smiles, an expression that looks both as synthetic as it does unfriendly. "I'm so glad that my brother has someone on whom he can rely."
John swallows uncomfortably, Mycroft's sentence finishing itself in his head with 'for discretion'.