There is a large section of the fandom that "ship" "JohnLock". For any of you that haven't got a clue what that means, they believe that John and Sherlock should be a couple. They have a great chemistry: they get on particularly well, and they both seem slightly jealous of each other's partners to start with. John asks Sherlock if he has a partner very early on in their friendship, and everyone assumes they're an item. Why is John Watson so keen to shout down anyone who calls him gay? Maybe because he really does love Sherlock, and he's tired of being reminded of the everyday pain that they can never be together. Maybe he's living a lie, dreaming of a blissful life with just him and Holmes. Maybe you're sick of the constant jokes about it, and you wish that once and for all, someone would put an end to the suggestion that Sherlock and John are secretly in love. But it would be one hell of a final twist if they were, wouldn't it?
