Sherlock and Moriarty are both beyond sex. To them it’s a petty animalistic need they look down on. They are both extremely intelligent and, I am sure, therefore well read enough in the subject of sexuality to be able to classify themselves as asexual in the common understanding of sex and pleasure.
However, this does not negate the fact that they perceive pleasure that is on the same level or perhaps beyond that which is the equivalent of sexual pleasure for ‘ordinary’ humans.
It is agreed by many a writer that “Sex is language”. In order to fit this particular argument, I’d like to take it further and say that pleasure is language.
There’s a common language many people speak. But more often than not, there are slangs, subcultural meanings, and sometimes altogether separate languages. Yes, I’m still talking about sex.
Moriarty and Sherlock speak the same language. It’s the language of tension, danger, attention to detail, use and stretch of the most powerful human erogenous organ - the brain. It’s the massaging and squeezing, the caressing and punching, the tying and releasing of that very organ with the challenge of the mind. This is their language.
This, where others would only be able to evoke boredom, they can each other evoke pleasure which ‘ordinary’ humans wouldn’t even know where to start in the attempt.
When Sherlock says he’s bored, it’s like when someone else says they’re sexually frustrated. The stimuli of knowledge and his brain in experimentation is like masturbation. Self-administered, short lasting, not entirely satisfying, but a bare minimum in pleasure. The more it is connected with an actual case, just like masturbation is more pleasurable with the imagination or rememberence or relativity to an actual sexually evoking happenstance or thought, the more pleasurable it is. When Sherlock deals with a complex case, it’s the equivalent of having a fling with a stranger. When it’s a serial offender, it’s like a short lasting relationship. But when Moriarty came along, it was like finding his soul mate. Like finding the only other human who spoke his language fluently.
It is safe to assume that the same can be said of Moriarty, except he plays a more active role in being a creator where Sherlock is mainly passive in his position as a chaser, analyser, finder. But the recognition of his orchestrations is lost on most. Moriarty has to, for so often an instance, be the only person aware of the finer details of his creation. And in Sherlock he has somebody who not only appreciates it and sees it all, but also someone who pushes him. He’s like a prostitute who has fine tuned skills of seduction which the ordinary customer doesn’t even register until someone comes along who has as much knowledge as them, can appreciate, respond, recognise, find pleasure and reciprocate.
What people don’t understand is that Moriarty and Sherlock are already lovers.