Contrary to what seems to be popular belief, John Hamish Watson is not actually gay. Yes, while he was stationed in Afghanistan, he might have experimented a bit; but then, who hadn't? You're away from your respective partner, you're lonely, so you mess around a bit, whether it's with a man or a woman. But he was absolutely 100% heterosexual, thank you very much. Okay, well, maybe more like 97%.
But just because he appreciates the attractive people that inhabit this planet we call Earth, even if they are decidedly men, does not mean that he's homosexual. John had nothing against homosexuality of course; his sister is a lesbian for God's sake!
He just did not appreciate it when people always seemed to think that he was in a relationship with Sherlock of all people. It's not a matter of looks or anything; Sherlock is quite attractive in his own alien way. But still; Sherlock Holmes.
Sherlock, who told him that he was, how had he put it? Oh yeah, 'married to his work'. Sherlock, whom he was almost positive was asexual; which would at least explean his lack of interest in either sexes, except for the famed Irene Adler.
John knows several people who are in love, or rather, fancy themselves in love with Sherlock. Yet they all register his obvious disinterest. Well, maybe not Molly Hooper. At least not entirely. But anyway, it just irks him when people automatically think that he's gy. Maybe that's what his appearance suggests, or just all of his mannerisms coupled with wardrobe. He had always thought jumpers were a relatively safe clothing choice. he isn't sure, but it can be irritating nonetheless.
John is now hungry. All this thinking about sexuality tenses him up and stresses him out. He eats a few slightly stale biscuits and polishes off the last of the loose-leaf Earl Grey tea. He must remember to pop out to the shop later and buy some more. Sherlock appears in the kitchen; wearing his sheet toga, presumably because he has yet again decided that clothes are dreadfully boring.
"I bought some of that yesterday. It's in the shopping bag on the table." Sherlock informs John, indicating the empty tin of tea before bustling about, making a cup of steaming coffee.
"Wait, did I hear that right? You went to a shop." John says incredulously, arching one pale brow in apparant disbelief.
"We were out oof milk. You were at the clinic. I didn't want to have to wait for you." Sherlock shrugs; looking slightly offended by John's blatant disbelief coupled with sheer amazement.
Johns nods slowly as though this is normal behaviour for Sherlock. He eats one last biscuit and starts to edge past his flatmate. John catches his foot on something and he trips.
"Really, John?" Sherlock asks, sounding utterly exasperated. He's gone and tripped on Sherlock's blasted sheet, and clusmy git that he is, has pulled it off him. John looks Sherlock's newly nude body up and down.
Okay, he's definitely gay.