A/N: If I'm honest, I hadn't intended to post this here and it's already over at AO3. But some people have been wondering about some of the background to 'Late Nights in Baker Street', so here it is. (Or at least, some of it. There's lots more where this came from.)

The first two months that John and Sherlock were together was the time of their lives - or at least, of Sherlock's life. Sherlock took cases, and John helped him at night, before they rolled into Sherlock's bed together. On one level, it seemed too amazing to ever end.

On another level, it was too amazing to never end.

The bomb in Baker Street happened to go off on a night that John was out hunting. (By hunting, he meant sneaking sips of blood off unsuspecting Londoners, but never enough to harm any one individual. He had been a doctor, after all.) However, he was still within hearing distance of the flat, having long-ago realised the damage that Sherlock could cause if left alone too long. (The wall was a fine testament to that.)

So when he heard the blast, only for a heartbeat did his thoughts drift back to Korea, and then he ran. (Though if Sherlock was dead, he knew that there was nothing that even he could do.)

Of course, Sherlock wasn't dead. There was hardly even a scratch on him aside from a cut over his eye, and the ringing left in his ears from the explosion. John kissed him, automatically licking the blood even against his better judgement. (He couldn't help himself, it tasted far too good.) After tidying the mess left in the flat, and assuring themselves that Mrs Hudson was perfectly fine (John had forgotten her in his rush to see Sherlock), they called it an early night and retired into bed.

But John soon had more worrying things on his mind than sleep. In fact, sleep soon seemed perfectly impossible.