A/N: Yes, I know this isn't a Johnlock, and I know that will automatically make this fic unpopular but if you're really nice you might still want to give it a chance? :) There isn't really any John/Mary Slash, it's mostly Sherlock/John Bromance and Sherlock/Mary Hate-mance ;D Anyways, hope you like it and I would really appreciate any kind of review! :D

Sherlock uncomfortably entered the restaurant and scanned his surroundings. The ambiance was dark with quiet music playing in the background, something one could consider "romantic", that is if one liked that kind of thing. He quickly found the table where his former flatmate was sitting by his girlfriend. Sherlock tightened his lips; he didn't know she was going to be here too. John had texted him to come there once he was finished with his case, that it was important, but seeing Mary Morstan was the last thing on his agenda.
To be honest, he hated her. Though it wasn't like she didn't feel the same way about him, in fact if it weren't for the sake of John, they probably would literally be at each others throats. Okay, he didn't hate her in an Anderson way, but he in no respect liked her, except maybe that she was actually quite intelligent for the average mind.

Sherlock wondered if he could just turn around and leave the restaurant. Too late; John had already seen him and was gesturing to come closer.
"Damn," he whispered under his breath, put up a fake smile and turned back to face them. Slowly he made his way over to table 24, in no way rushing any of it. Curiously he watched the couple happily talking to each other, both of them dressed in quite fancy clothing. Sherlock cocked an eyebrow. Finally he arrived at the table.
"Sherlock!" said John happily as Sherlock took the seat opposite the two. Sherlock's "smile" widened but he said nothing.
"Sherlock," Mary said with less enthusiasm. Sherlock had to admit, when it came to acting as if she liked the person in front of her, she was almost as good as him. He wondered if John even knew about their inner wars.
"So," the consulting detective said, "Why have I been summoned?"
"Well," started John, "We wanted to tell you something." Sherlock raised his eyebrows.
"And I'm here, so can you get to the point?" John was about to say something but then Mary put her hand on his lap and shook her head. Sherlock's lips tightened even more and he narrowed his eyes in disgust.
"Oh, but I have to go to the bathroom first." John looked at her than nodded with a tiny smile.
"Yes, yes of course." She gave him a short kiss on the cheek, which made Sherlock almost feel sick and got up, her black dress flowing gracefully behind her.
"So, how's the flat? Or did you destroy it again since the last time I saw you?"
But Sherlock wasn't listening. He was carefully watching Mary, waiting for her to be out of site.
"You know, even though I've moved out, it doesn't mean that I don't want to come with you as least often as I can. You can always just-" Sherlock shushed him. John looked at him confused.
"What is it?" The tall man turned to him and bended over closely so that they were eye to eye.
"Mary; didn't you notice her hand?" John didn't quite seem to understand where this was going.
"What about it?" Sherlock sighed, but kept his serious look.
"Left hand, annular finger; There was an engagement ring on it."
John stared at him in shock.
"John, I have reason to believe your girlfriend is cheating on you." John blinked a couple times, and Sherlock could feel his now quicker breaths against his face.
"Are you absolutely sure that was an engagement ring?" he asked.
"Positive." Somehow, he didn't find those sentences in any way hard to say.

In that moment, Mary returned to the table. She seemed puzzled as to why the two men were so close to each other. John looked up to her and pulled himself back, gesturing her to sit. She did so.
"Mary, I need to talk to you." Sherlock leaned back in his chair and stared at her with pleasure. Busted, he thought with a clear smile.
"What is it, John?" she asked. His look was extremely harsh and she stared back at him in a confused and worried manner.
Just before he said anything, his look soften again and so did Mary's.
"Guess what...? He bought it." Mary looked at him in shock for a couple seconds and John's up-to-now completely straight mouth cracked into a huge grin. Sherlock shook his head, making sure what he was seeing was correct.
"Wait, what?" he asked.
Suddenly the couple burst out in laughter and fell into each others arms. Tears fled their eyes as they continued their hysteria. Sherlock watched the two giggling harshly for at least one full minute until they both took deep breaths and turned back to face him.

"What just happened?" asked Sherlock bewildered.
"She's wearing an engagement ring because I proposed to her, idiot." Sherlock stared at the two speechless.
"But... I thought you would've told me..."
John grinned again.
"I did, you weren't listening, so instead I decided to tell you later."
"But then I had the idea," Mary continued, "To see if you would think I was cheating on him by wearing the ring in front of you."
"I have to say though, neither of us thought it was actually going to work." Sherlock felt his face flush in embarrassment. He bit his lip while avoiding both gazes.
"Fine, you got engaged. Whoopee, was that the only reason why I was told to come here?" Mary's smile almost instantly dropped. John sighed lightly and then said softly:
"Of course not, now that you know I need to ask you a favour."
Oh no, anything but that.
"As my best friend, Sherlock, will you also be my Best Man?"
I knew it.

An inner battle started in Sherlock's head. Of course he didn't want to be a bad friend, but then again attending a wedding was the last thing he wanted to do, on the other hand John had always been there for him when he needed something from him, however ridiculous it was, but still, the idea of people dancing and drinking and talking and being happy simply revolted him. He crinkled his nose yet still managed a smile.
"Of... Of course." John smiled at him and Sherlock could feel Mary's gaze resting on him.
"Great! I'll go ask for some wine to celebrate," he said while getting up. Sherlock rolled his eyes, instantly regretting what he'd gotten himself into, but before any more thought to it crossed his mind, he felt a knife pin his coat to the table.

His head whipped around staring down at the blade holding his arm down, and wide-eyed glanced up the arm holding it in place, finding an extremely angry looking Mary. Of course he could've told her all the witty lines popping into his head, and figure out some nasty things about her in the blink of an eye but something stopped him. And perhaps (that's a very big perhaps), that something was called fear.
"Listen," she said sternly, the usual Mary completely gone, "You know perfectly well, that I don't like you very much." She practically spat the words out. He tried to pull himself free but she was far stronger than she looked.
"But this is what John wants, and if he's happy, I'm happy... And I promise you, if you do anything to ruin the wedding..." She pulled the knife out demonstratively. Sherlock knew very well that she wasn't actually threatening his life (too bad, he could've reported her then), but he in a way felt intimidated by the woman sitting diagonal from him. Maybe her being able to intimidate him impressed him, made him gain more respect for her, but Sherlock was still far from liking her. After all, she had just planted a knife in his sleeve. Mary's look softened immediately the moment John came back quickly followed by a waiter who was carrying a bottle of fifteen year old wine with him.

Sherlock fiddled with the tie he'd been forced to wear while John nervously paced up and down in front of the altar. Mary had insisted on it being in a church; typical. None of the guests had arrived yet so it was only the tall, brown-haired Best Man sitting in the front row, and the notably smaller blond groom walking in front of him. Sherlock counted about seventy back-and-forths before finally saying:
"Why are you so nervous?" John finally stopped pacing and stared at him. Sherlock rolled his eyes.
"I know, I know, human love, you only get one wedding, at least with that person, which again doesn't seem to be true, and everything has to be perfect, blah blah."
John said nothing for a while.
"Could you just..." he started the sentence then trailed off, staring down at the white rose carefully placed in the chest pocket of his suit.
"What? Not be myself?" asked Sherlock as if he'd said that sentence a million times before. John smiled softly.
"No, I don't want you to not be yourself. I... I want you to just keep in mind that this might be the one day in my life that isn't about you. And... I'd just like it to stay like that the entire time."
Sherlock stared at him puzzled, and for some unknown reason, he understood. Today was about John (oh, and Mary), and as Best Man it was his duty to make sure that it would be.
"I'll do my best. I promise," he said while nodding, and got up so that they were now both standing. For a while the duo just looked at each other, recalling all the time they had passed together in pleasure. In a way, this was also a big step in Sherlock's life. His best friend was leaving him for a good.

No I'm not! the voice that sounded like John echoed in his mind. No, he wasn't. But still, once the vows were said, once the rings put on, the moment he kissed the bride, nothing between the two would be the same again. They would no longer be The Consulting Detective and His Blogger, maybe their cases together would grow even fewer than they had since John had moved out but one thing was absolutely, one hundred per cent sure: They were, and would always be best friends. Just before the priest arrived the two fell into a quick hug, and surprisingly, Sherlock didn't feel uncomfortable.

"...I do."
"I now pronounce you husband and wife. You may kiss the bride." Sherlock let out a blow of air, which luckily no one heard as exactly in that moment the organ started playing again and every single person in the church except for him and a few of the toddlers got up and cheered as the newly wedded couple walked down the isle, hand in hand. Even though Mary was smiling at John, Sherlock felt as if she was carefully looking at her, and quickly he got up as well and clapped with a smile. He couldn't believe he'd just bared through that entire thing and his signature was now in that book, saying that he truly believed that John Watson and Mary Morstan, were in love. That in it self was a lie, as Sherlock knew exactly that true love was but a fairy tail, invented to give children hope that their life wouldn't turn out as miserable as it did... Still, he needed to stay in a good mood, for John (and so he wouldn't have to feel the wrath of the new Mrs Watson).
The freshly married couple made their way to the door and got outside.

Sherlock had to pose for far too many photos than he thought were necessary, and still suddenly he found himself leaning on his right arm on the table in melancholic manner to the left of John. It wasn't the traditional way of sitting but John had thought it would be nicer for him to sit there, as Sherlock knew basically no one at the reception. Wrong. No spot in the entire ballroom would've made him in any way less bored. It also wasn't just boredom, he felt a little left out on the whole thing. Maybe it was just because weddings weren't his thing, but it was like everyone had a place here except him. He was the Best Man, the third most important person at the event and yet he had never felt as useless as then. And there was another problem: He was meant to give a speech after the first dance, something moving, inspiring, something that said something about their love. Only problem was he was probably the worst person in the world for that. But he didn't want to mess up, he wanted to make his friend happy, not make this about him, not get a knife cut in his borrowed suit. But how could he do that?

The DJ announced that it was time for the first dance and a song Sherlock didn't know (what a surprise!) started playing. It was soft and melodic, and as the two slowly walked onto the dance floor, Sherlock could feel the rest of the room slowly swaying along to the rhythm. He observed as John and Mary's hands interlocked and she gently placed her head against his shoulder while their feet slowly turned around. In his chest pocket, Sherlock felt his phone buzz. As discreetly as he could, he pulled it out and checked the text he'd gotten under the table so no one would notice.

Triple murder on Oxford St
Need your help. Please come as quickly as possible.

Sherlock looked up. Maybe this was his chance. Surely no one would notice, and he wouldn't have to worry about that stupid speech anymore... He pushed his chair back as quietly as possible while putting his phone back into place. Just before getting up though, the two spouses had made a full turn, which meant Mary was facing Sherlock again. She was smiling but something about her look told him she knew what he was doing, and it looked more than a little menacing. Sherlock pursed his lips and pushed his chair back into position. Again he was leaning on his hand while absently watching the two slow dancing to the music.

"It's gross, isn't it?" The high-pitched voice made Sherlock jump. He frantically looked around himself and found a small dark-skinned boy wearing a tuxedo and a bow tie staring up at him. Curiously he looked down to him.
"I wouldn't use the term 'gross' per say," he turned back carefully watching the doctor and his wife as they kept spinning in slow-motion, "but I'll admit I don't find it very appetizing." The boy looked up at him with a tilted head.
"Say, aren't you the Detective-Man?" he said pointing at him. Sherlock smiled proudly.
"Yes, yes that's me. Sherlock Holmes, at your service." He held his hand out and the child shook it, his expression clearly excited about meeting a "celebrity".
"I'm Mickey, can you do the deduction-thing, please Sir?" Sherlock was about to open his mouth and blurt out everything he came up with, release him from his eternal boredom but then he remembered what he'd promised John and he was not about to go back on his promise.
"I... I can't, not today, I'm sorry. But if you want you can come over to this address and I'll show it to you, all right?" He said while writing down '221B Baker St' on a paper napkin and handed it to the boy who took it and smiled back at him.
"Thank you, Mister Holmes." And with that, Mickey left and Sherlock was again left with no one intelligent to talk to. That boy was perhaps the only other person in the room who didn't believe in true love, probably for different reasons than he did but still, it was nice to have that in common with someone.

Great, now I also have to live up to that promise as well... I can't really just hush him away if he does show up...

Sherlock resumed watching the couple dancing, but this time he didn't just see; he observed. Watching the two in each others arms, every single part of their body language expressed security and comfort. He didn't think that he'd ever seen either of them as happy as they were in that moment (although that may have been because Mary was never especially happy when he was in her presence). They were so happy that those two were the entire universe, and Sherlock was just a quiet watcher from the outside, who even if he had wanted to, couldn't have penetrated the wall between him, and John and Mary. And that was the moment when a tiny part of him, probably the part of him that had stopped him from doing anything attention-seeking that day and had forced him to sign that bloody book, did believe that these two were in love, that they truly loved each other and that they wanted to be together. And somehow he understood, though he hated to admit it to himself, that this was all not to their disadvantage.
All it was, was love.
It was as simple as that, and yet he had taken all his life to solve that puzzle. Just for a couple moments more, he got to stare at the two a little longer, letting them infect him with his happiness, forget what he was, forget who Sherlock Holmes was, forget everything and just be completely happy, even though he wasn't supposed to be the happiest man alive on that day. But then, the song ended and Sherlock realized that the couple was returning to their seats, and before he knew it, all of the eyes in the room were resting on him. Sherlock gulped and slowly stood up, not knowing what to do. Suddenly he felt a microphone being pushed in his hand and looked down, seeing Mickey nodding at him respectfully. Sherlock turned his head to the other side where John was sitting looking up to him.
"You'll be fine," he whispered.
No I won't.
"Thank you, John." Sherlock took a deep breath and looked around the room, careful choosing his words.

"I have to admit, I'm not a wedding person. But... that doesn't matter. Today, on this eleventh of June 2013, it doesn't matter what I think, or what he thinks," he pointed to Mickey who was still standing next to him, "or what any of us think. Because... We were not invited to this celebration so that we could give our opinion on these two new people, who have chosen each other, under the seven billion other people they could've chosen, and let me tell you, I am able to calculate the odds." The entire room chuckled lightly. "But we've been invited here to witness the happiness that Mary Morstan and John Watson have found in each other, and be happy not just for them, but with them. Until today, actually until just a couple minutes ago, I don't think I understood that. I probably won't ever understand love in its total depth but as I said, today is not about me. Today is about Mary Watson, née Morstan, and John Watson, my best and most trusted friend, and it's about them deciding to take their next step into life together." And it's about me taking my next alone. The thought felt like a tiny stab but again that John-like voice in his head told him that wasn't true, told him that Watson and Holmes would never be over.

The entire room had been completely silent while listening. Sherlock nervously looked around the room and added, "That is all" before sitting back down. He closed his eyes in embarrassment when suddenly everyone started cheering in agreement and he looked around in confusion. John was holding onto his arm gently and glancing at him with moist eyes as he said:
"I knew you could do it." Sherlock smiled widely at him, and for the first time that day, it felt completely genuine. Mary was smiling a genuine smile at him too, and she pushed her seat back, lifted the long white dress and made her way to him. Before he knew what she was doing, Sherlock felt her skinny arms wrapped around him. Were they at peace or something now?
She tilted her head so she could whisper into his ear.
"Nice job, idiot."
So no peace. Seemed more legitimate. But that didn't matter. He hadn't been planning on it anyway.