Sherlock was quite happy with the next few months, although he was starting to worry about John. As much as he swore that every time they got together would be the last, there was no end in sight for their assignations, and it was beginning to wear on poor John. He clearly disliked being unfaithful to his wife, and Sherlock almost felt guilty.
Almost.
It was another one of those mornings when John had come over to help on a case, and they barely made it past the bedroom door, John dropping to his knees and unzipping Sherlock's fly. They didn't notice – or care – that the door was left ajar or that Mrs. Hudson was just downstairs.
John was a rather quick study, as Sherlock found out, learning to do the most intricate things with his tongue, driving Sherlock to the point of insanity before even taking his cock into his mouth. Sherlock vaguely wondered if John had done research, because that flicking motion at his perineum sent shivers up his spine. When John finally covered Sherlock's glans with his lips, Sherlock was on the verge of orgasm.
"John? Mrs. Hudson said I could…" Mary's voice trailed off, her already pale skin suddenly completely devoid of color. For some reason, the sight of Mary's blue eyes lingering for a moment longer than was necessary on Sherlock's hard cock, combined with John's horrified face, only spurred Sherlock on, and he came undone, spraying whitish fluid on John's bright red cheek.
He smirked at Mary through a post-orgasmic haze, as John lunged upwards, forgetting to pull on his trousers, which pooled awkwardly around his ankles.
"Mary! Mary, I…" John started, wiping his face, but the look of icy hatred she shot at him shut him up instantly.
"Harry is in jail." She spat at him through tight, quivering lips. She paused for a moment as she turned to leave and said "Don't follow me. And don't come home tonight." The door slammed behind her, and John's world turned upside down.
"Are you actually smiling?!" John yelled at Sherlock while pulling up his trousers.
Sherlock couldn't help himself. The whole affair was so ridiculous, and though he understood that it must be painful for John, it was all he could do to grin instead of laughing out loud.
He composed himself and said "You're welcome to stay in your old room until things blow over."
John shot him a look of pure venom and stormed out.
John stayed at Harry's that night, after bailing her out for yet another drunk driving incident. He didn't have the strength to tell her what had just occurred, and he didn't feel obligated to do so, considering her predicament. She knew better than to pry.
He was allowed back home the following day, but Mary treated him with cool detachment. He apologized profusely and repeatedly, but she merely ignored him except to say "pass the salt" or "are you finished with the newspaper?" Still, he supposed it was a good sign that she had allowed him to sleep on the couch and hadn't filed divorce papers just yet.
He had had no contact with Sherlock, and was simultaneously relieved and concerned that Sherlock hadn't so much as sent him a text.
The fourth morning after 'the incident', as John now called that incredibly awkward moment in his head, Mary called after him as he stepped outside the house to head to work.
"Be home by 7," she said.
John stood flabbergasted for a moment, unsure how to react, then turned back from the door and asked, "Why?"
"You said you wanted a chance to make it up to me." She said. "Be home at 7." Her expression was inscrutable.
John cleared his throat, frowned at the wall, and felt something like joy mixed with fear in his belly. "Alright." He said.
Sherlock was playing his violin when he heard her come up the stairs. He was expecting her.
"Tea?" he asked before turning around to look at her. She wore a grey A-line skirt and a red blouse with triangles cut out at the sleeves so her bare shoulders protruded out of it. Her hair was arranged in a tight bun up on her head, with a few curly tendrils framing her pale face. She wore bright red lipstick to match her blouse. For a moment she reminded him of Irene. That was a first.
"No, thank you. I'm here to talk business." She said.
They both sat down. "You have thought of the perfect punishment for him." Sherlock said looking at her with those piercing eyes. She flushed a little but returned his gaze steadily.
"Yes." She exhaled. "If John is right about you, you already know all about it."
Sherlock allowed himself a small smile.
"Naturally. I'd still like you tell me the terms of the agreement." He replied.
She nodded and began to talk.