Parties are definitley not Sherlock Holmes' thing.
They are hardly John Watson's thing either, but John is hardly Sherlock Holmes; he is actually capable of understanding the concept of doing-things-you-really-don't-want-to-do-but-do-anyway, of pleasing the people around him, of common courtesy. Sherlock, however, avoided most social gatherings and all boring things. And, my God, parties are boring. The catch is that Sherlock also avoided avoiding John at all costs, which is why Sherlock was leaning against the front bar table of a run-down, tacky bar in London, swigging back his second shot of whiskey, and trying to subtly sneak a wiff of every exhale of cigarette smoke possible since John insisted on attending a Christmas party for Scotland Yard.
John promised Sherlock he would have fun, which Sherlock denied and listed all the reasons he wouldn't on the cab ride over. John also promised he would not leave Sherlock's side, which left Sherlock extremely annoyed when John meandered to the complete other side of the party before Sherlock even ordered a drink. Sherlock was passing the time by deducing which party guests were having an affair, which was a shockingly high number, when Mycroft found his way next to him.
"Well, this is a surprise, brother-mine," he commented, far too cheerfully. He was obviously delighted to see Sherlock at a party, noticeably uncomfortable and unhappy. Sherlock's displeasure always pleased his brother, and vice versa. Mycroft and Sherlock may be incredibly unique individuals, but their sibling rivalry was nothing obscure.
"Mycroft," was all Sherlock said with a sigh. Sherlock's eyes focused off of a woman who's left ring finger was still discolored from a wedding band - either a recent divorcee, but more likely a participant in an affair, that makes her number twelve - and focused on John. He was chatting up a tall brunette, of course, and he looked simply chuffed, which is how Sherlock loved to see him, though he would never admit it. That's obvious, isn't it, that a man would want to see his best and only friend happy? And obvious is boring, and boring is meaningless, and John isn't meaningless, so some things go left unsaid and simply assumed.
Mycroft ordered a drink, though Sherlock figured he would not drink it, or only take a sip or two. Mycroft was not a drinker, and more importantly, watched his weight and worried about his health far too much than to let such a bitter depressant enter his system. Sherlock was too entranced by John to make a snide comment, however.
Why was Sherlock feeling this way? John was simply speaking, quite animatedly, but he looked so... beautiful. Which was a strange adjective to pop into Sherlock's head, especially about another human being. But this was John, and he was not just another human being. And he looked beautiful. In that moment, in that tacky bar, in that small, crowded room, being so happy and kind, he looked beautiful.
Sherlock suddenly felt his brothers eyes on him, and he realized he was smiling. Not grinning, open mouthed, but a small, fond smile was on his lips, and he suddenly felt odd. He knew there was no point in trying to hide it; Mycroft was fairly clever, whether Sherlock wanted to deny it or not, and could pick up on Sherlock's embarrsassment in a matter of a second. His smile had fallen, but he continued to fondly watch John, who was now searching the crowd for someone, probably Lestrade. John and "Greg" got along well, and John probably wanted to chat with him.
Sherlock, still aware of Mycroft's gaze, decided to question it. "Is something on my face, or shall I humor you?" He turned to face his brother for the first time that night, and met Mycroft knowing eyes with his cold, wavering ones.
"You humor me everyday, Sherlock," Mycroft quipped, and turned to look in John's direction. Sherlock turned as well, and was met with John's pale blue eyes. His heart skipped a beat, which was a new experience. Sherlock realized that John must have been searching for him in the crowd, which made him feel... funny. Which made his brain feel funny because he never felt funny. Why does he feel funny?
John gave him a big, warm smile, one that always reminded Sherlock of the day they met, after returning to 221B after running all over London, failing to catch the cabbie. They had a giggle fit, and it was the first time they ever laughed together. The moment when Sherlock realized John was special.
Lestrade approached John and he turned away, already in a deep conversation with him. Sherlock still stared, almost feeling invasive, but he could not help it. John was so watchable, like how idiots go out bird watching; John was a beautiful, sweet bird and Sherlock wanted to admire him from afar for the rest of his life.
"You love him?" Mycroft suddently asked, quietly but surely, turning to face Sherlock. His eyes twinkling; he already knew the answer to the question, but he wanted to hear his brother answer him. Part of him was over the moon, ecstatic that his brother finally found someone, finally found happiness, finally found love.
"Mm," Sherlock replied. It was more of an idle thought reponse, like Sherlock did not really hear his question, which did not surprise Mycroft since his brother seemed so transfixed by the doctor. Mycroft just smiled warmly and repeated his inquiry: "You love him?"
There was a pause, but it did not feel like an unsure hesitation, but more like a deep realization, like everything was falling into place.
"Obviously," Sherlock breathed.