John knew he had picked up at least a bit of Sherlock's observational skill, but he liked to think he kept his previous level of tact. Therefore, when he observed the thin gold ring around Mycroft's fourth finger, John tactfully avoided mentioning this fact until Sherlock managed to drive Mycroft out of 221B and he and Sherlock were left alone.

"Sherlock." John waited until the downstairs door closed, but only barely. "Sherlock, he was wearing a ring."

Sherlock hummed noncommittally. "Yes, he does that."

"He's never worn a ring before. At least not that I've seen. Why is he wearing a wedding ring?"

"It's his anniversary."

John stopped dead. "Mycroft is married?"

"Was," Sherlock replied. "His husband's been dead - oh, nearly seven years now. He still pulls out his old ring on their anniversary each year."

John felt for a moment like he was flailing about underwater, like Sherlock and Mycroft and the rest of the world were happily playing on land above his head and had no clue why he wasn't able to breathe air like the rest of them. "I don't-" He took a deep breath. "Mycroft is - was - married. To another man. Why did I not know this?"

"Technically it was a civil partnership," Sherlock said in a bored tone, not looking up from his position on the sofa. "And you didn't meet me or Mycroft until after his husband died, ergo you never had a need to know about him."

"I-" John stared at his flatmate, then wandered over to flop heavily into his armchair. "You do realize it's possible to want to know information about someone just because the information gives you a more well-rounded picture of them, not because you're solving a bloody case, don't you?"

"Obviously." Sherlock sat up, propping his elbows on his bony knees and finally looking at him. "What do you want to know?"

"What was his name, for one? Anything as strange as 'Mycroft' or 'Sherlock?'"

"Severus, actually."

John's breath left him in a huff which could have been a laugh. "Wow."

"He was a teacher," Sherlock continued. "Lived and worked at a boarding school for gifted students up in Scotland most of the time."

"I'll admit, I can't see Mycroft falling for a teacher type."

"He wasn't just a teacher." Sherlock's lips turned up into a smirk. "Or rather, I should say, he was a teacher in the same way Mycroft occupies a 'minor position in the British government.'"

John frowned. "So what - a political mastermind? A mentor for little future Mycrofts?"

"Lord, no, nothing like that."

"A spy, then?"

Sherlock shrugged. "That was my assessment, yes. Not one of Her Majesty's, obviously, but on the right side in the end."

Obviously? John let it slide. "'In the end' - was he killed in action, then?"

Sherlock snorted. "Snakebite, if you can believe it. At least, that's what Mycroft tells me."

"You don't believe him."

"How often do you really come across venomous snakes in Scotland, John? No, I don't believe him. I suspect Severus was poisoned by whoever he was spying on. But the whole thing sounds like a secret cold war - no overt position taken, by Mycroft's people or by anyone else." He shrugged one shoulder. "Believe me, I checked. Mycroft could have been making the whole thing up, for all I know."

"I doubt he'd do that." John frowned. "Christ, I just can't think of Mycroft married. I mean, it's not like he'd ever be able to talk about his day. Or even what continent he'd be on later that week. Living with you is hard enough . . ." He snapped his mouth shut before he said something he'd regret later, but Sherlock seemed to both understand and not mind.

"Severus was . . . different." Sherlock stretched his long legs out, ankles crossed, and leaned back against the sofa cushions. "I didn't know him that well, of course, but from what I did see, he was a good match for Mycroft. Could practically read his mind, which means there was finally someone besides me who could see through Mycroft's bullshit."

John coughed in surprise. "Sherlock! I don't think I've ever heard you swear before."

"It happens more often when I'm in proximity to my brother."

They both sat in silence for a moment. It really was odd to think of Mycroft as married - as sharing something that intimate with someone. A thought flashed through John's brain of exactly how "intimate" marriage to Mycroft might be, and John shook his head sharply. Not a mental image I want. Ever.

"So why does he hide it?" John finally asked. "And then why does he wear the ring?"

Sherlock shrugged. "Why does anyone do illogical things? Sentiment, I should expect. They hid it most of the time they were married, too - I got the impression parents would have been unimpressed if they found out their children's teacher was gay. And Mycroft was always worried about someone trying to use Severus against him."

"But he wears the ring now?"

"Once a year, yes." Sherlock made an annoyed noise. "Why are you asking me this, John? You know I'm usually rubbish at this kind of thing."

"Right, well that's true."

"Satisfied your curiosity for the meantime?"

"I suppose." John stood up and headed for the kitchen. "Tea?"