When he met Watson he had no idea. This lack of understanding was probably what he found so immediately engrossing and attractive about him. He couldn't put his finger on it but, something was not right about the man. He didn't know until too late that right from the beginning he had been stabbed in the heart. One day he suddenly found he was in love with a violent creature who hid in the dark rooms of his home.
So, Holmes did not turn him in when, early in their relationship, he figured it out. The good doctor enjoyed strangling their prize catches just a touch too much. That he had fallen for a potential murderer did not frighten him nearly as much as the irrationality that love brought with it. He tried to justify his unreasonableness. It was not as though Watson would cheerfully wander the streets killing. In fact, although they never breached the topic in conversation the detective was sure that he was deeply ashamed, worried that one day he might go too far in his play and murder someone.
Sherlock comforted him as well as he knew how, articulating in an obtuse way that he too had always been attracted to the macabre. That to him there is something unnameable and morbidly seductive about murder. It was, after all, the last taboo, the most dangerous game one could play for both the perpetrator and the victim. And therein lied the thrill. The image of a killer climbing in through an open window, stalking his prey, knife shining in the moonlight had always sent shivers down his spine.
Watson only responded by laughing as he conjectured that he had never seen it that way before. In fact, he had always been convinced he was just an incurable misanthrope. But, it seemed obvious after Holmes had explained: there could be some twisted affection in such dark urges.
Sherlock thought he had lost his mind when he finally brought the topic around. Though, it seemed like the natural thing to do at the time. He tried to sound as calm and disinterested as possible when suggested that Watson satiate his blood lust by smothering him. In all honesty it was to satisfy his own curiosity as well as his partner's.
It didn't take long to convince him it was the right course of action. It never did. His heart raced as he accented the narrow stairs to his friend's bedroom, faster than it ever did in even the most highly charged case. He knew this was as stupid as it was risky. Yet, there was something incredibly satisfying about unraveling his lover, reading him and digging up a part of him buried so deeply that nobody else in the world had ever seen it before.
With their legs touching they sat beside one another on Watson's tiny bed and agreed the safest way would be for Watson to use his hands. Sherlock tried to relax as his partner secured the crook of his elbow around his neck and covered his mouth and nose with his palm. For the first long moment there was nothing. Then he became dizzy, his vision narrowed, his lungs burned for want of air. Watson held fast. Sherlock valiantly staved off panic before finally trying to struggle away. Watson's grip remained for what seemed to Holmes's oxygen starved mind like an eternity before he let go.
Holmes gasped. Never had he been more happy to have take in the simplest of biological imperatives. Between the two one was breathing just as erratically as the other. Both men's pupils were equally dilated, both men's cheeks flushed with similar excitement. They decided since that really it was rather fun and they should try again. This time as Holmes struggled and his vision blackened Watson did not release him. When he woke it was to his friend's horrified apologies. Holmes, equally as terrified at what he had witnessed of his friend's savage nature, felt he could not properly express himself in English. French would have to do.
"C'est rien," he lied calmly, "Mon cher, ce qui est une petite mort entre les amis?"
