For Schermionie's 5, 10, 20, 50, 70, 100 Fandoms Challenge.
Sherlock Holmes had an extremely low tolerance for those with a lower IQ than him. Which, in his case, meant that he didn't really like anyone, save Mrs. Hudson, and that was only because she was lovely, always cleaned up after him and made a wonderful cup of tea.
When John Watson came along, nothing much was meant to change. He was interesting enough to analyse during their first meeting—all war veterans were, but after those few seconds, John Watson was supposed to become just another dull memory of Sherlock's.
Needless to say, that wasn't quite how things worked out.
John moved in and Sherlock found that he simply couldn't ignore his presence. Of course, he was terribly annoying and dimmer than anything, but even Sherlock had to admit that there were certain aspects of John that one could consider interesting.
His studious nature, yet complete inadequacy to make simple deductions, was incredible. His desire to seek out danger and adventure was both curious and completely mental. His social activities...well, Sherlock didn't understand those at all. What sort of person would want to interact with others in such a frivolous manner? What sort of person had the patience to handle fickle-minded women?
Sherlock had developed several theories on the odd behaviours of John Watson over the past weeks and had found a common trend: that Doctor John Watson was just a little bit insane.
It was this insanity—this slight touch of madness that even Sherlock couldn't understand—that compelled Sherlock to keep him around. Because although his inability to use common sense was infuriating and his IQ was most certainly not satisfying, John Watson was interesting. He strove to improve. He got his kicks from chasing murderers and waving his gun around like nobody's business.
And sometimes—just sometimes—he had the ability to surprise Sherlock.
Only sometimes. But those sometimes were enough to make Sherlock want to keep John around, stupidity and all.
