A fill for this prompt on the livejournal Sherlock Kink Meme:
I have a craving for some humor as well as time travel fic.
John from the future, somehow, goes back in time to slap around his younger self and tell him that he's not actually as straight as he thinks he is and to get with the program you idiot.
bonus points if he's married but doesn't say to who.
John breathed deeply. It was so good to be in London again. He hadn't had the chance to return as often as he liked now that he was retired. Well, in the future when he was retired. John Watson was not only traveling back to the place where his life began, but the time as well.
The beginning of his life was ironically around the time when he was fresh from the greatest threat of death he had experienced. He still had the scar in his old age, but the ridges of raised skin on his shoulder were not as prevalent anymore. The start of his life had nothing to do with his physical being. It had everything to do with Sherlock Holmes.
John from the future, called Jawn to avoid confusion, was taking a walk through time to straighten some things out.
Hm. "Straighten" probably wasn't the best choice of words.
Jawn still had his keys to the flat, so he let himself in to 221B. The decency to knock at the top of the stairs did not escape him, though.
"Come in, Mrs. Hudson," a bored voice said within the flat. Some awkward position of the sofa, judging by the strain in his tone.
"Not Mrs. Hudson!" Jawn called through the door.
"Don't be ridiculous, John," Sherlock was sitting up now, his sound had changed angles. "Everyone else rings the bell. Except Mycroft. The cake-munching sod simply walks in."
"Were you saying something, Sherlock?" John from the present tense entered the sitting room. There was a pause as Sherlock processed the dual source of John's voice.
"There's someone at the door, John," Sherlock said. Jawn could already picture his fingers steepled like we're when he came across something perplexing.
"You called me for that?" John strode to the door. "You were much closer, honestly, I don't-"
John didn't finish his thought, it died in his throat when he saw... himself on the other side of the door.
"Hello," Jawn said brightly. "Should I invite myself in? Or you could. It's all the same to me." He smiled.
John's pupils did a strange dance in his head. He closed his eyes, gave his head a shake, and, when he saw that the oddity before had not vanished like it was supposed to, turned to his favorite chair and proceeded to curl up in it.
"Are you still Dr. Watson?" Sherlock asked from the sofa.
"Why do you ask?" Jawn returned.
Sherlock stood, adjusted his collar of his shirt, and laid out his logic. It was rather nostalgic for Jawn. "You are wearing a wedding band. There are no traces of lipstick or perfume about your person, but you have a quarter-shaped bruise at the base of your neck. You have seen your lover recently, but that person does not wear cosmetics. Your clothes are fairly new and your watch is not cheap. The lack of cosmetics is not from necessity, suggesting a male companion. Did you take his name when you married, or keep your own?"
"Now wait a minute-" John sat at attention in his chair.
"I love it when you deduce me like that," Jawn spoke over him. "And yes, we both kept our names."
"Just who are you?" John still looked confused.
Sherlock rolled his eyes. "Isn't it obvious, John? He's an older you."
"That's right," Jawn confirmed. "Come closer if you don't believe me."
John did so, stepping cautiously. "Bloody hell, it is me," he said after a minute, taking in the greys mixed with his blond, the continued awful taste in jumpers and the lines on his face that he saw on himself every morning.
Jawn beamed. "Now that that's settled," he handed a camera to Sherlock, "I'd like to get a picture with myself. For the husband, if you don't mind."
Sherlock looked rather amused. "A paradox. How not dull."
"As long as it doesn't rip a hole in time and space," John muttered, shuffling to stand next to his counterpart.
Jawn chuckled and waited until Sherlock was ready. At the last moment, he reached for John's chin and pulled him into a kiss. A choking sound came from Sherlock's direction, followed by many shutter clicks. John blanched and struggled, but Jawn kept him in place with a hand on the back of his neck. When the aura of Sherlock's amusement faded into annoyance, Jawn gave a final nip to his lower lip, just the way his husband often kissed him, and drew back. John looked absolutely horrified.
"Dare from my other half," Jawn shrugged, his wedding band glinting in the light of the flat. "Hope it wasn't too bad for you." He winked.
"I'm not gay!" John protested. His face was red and his arm shook slightly as he wiped his mouth.
Jawn sighed. "That's what I'm here to convince you otherwise."