John watched Sherlock sleeping on the sofa. The case was over and this was the post- crime- solving crash. He might sleep for a few hours. He might sleep for days. John had covered him carefully with a blanket. And waited.
Sherlock looked so beautiful when he was asleep, no other word for it. Beautiful. All elegant lines and graceful angles. His face relaxed and handsome. It made John's heart hurt. And it also fuelled John's own self doubt. The things he never talked about. Because he wondered if one day Sherlock would find him boring like everyone else Sherlock had ever known? Or worse, not boring, but just decide he hated him, like he had done with Mycroft. Or worse, find that John was no longer of any use. And then what was he going to do? Perhaps, thought John, he needed to leave now. While he still had a chance of getting out in more or less one piece. Because the longer he stayed, the longer he risked total annihilation when Sherlock decided it was all over.
Sure. It was all fine now. But John knew from bitter experience that it didn't always stay fine. Especially it seemed if you added John Watson into any relationship equation. There was the girlfriend who left him for his taller, better looking friend in the first year of Medical School. There was the girl who promised she would wait for him when he left for his first tour in Afghanistan. She had in fact waited a week before informing him via email that she was now going out with a Captain in the Guards. There was the girl he met on leave in Brighton who he had spent two weeks taking out to dinner and making passionate love to in a variety of expensive places. Who never even wrote to him. And all the other relationships before and in-between. They all decided he wasn't worth the effort.
Sherlock shifted a little in his sleep. John sighed and seriously considered packing his things and going. What did he think he was doing? How could that amazing creature asleep on the sofa ever be his? John stood. Unable to watch any longer because the lump in his throat was threatening to strangle him.
"John?" Sherlock's voice was sleepy.
"Yes?"
"You're not leaving are you? Please don't leave me." John wasn't entirely sure Sherlock was awake.
"I won't."
"Good." A long arm pulled John down onto the sofa. "You really do think too loud John."