A/N- Inspired by a post from bbcsherlockheadcanon tumblr.
John lifted his hand to his neck, fingers instinctively searching for his dog tags. The digits met only bare skin and he was one again reminded that he no longer possessed them. Sighing, John brushed the unconscious gesture away and continued with his day.
John did not always wear his dog tags. Sometimes the memories attached to the little pieces of metal weighed him down and he would pull them off in frustration. They would then live in a drawer next to his bed for a few days until he felt ready to shoulder the memories again.
Two days before Sherlock died had been one of those days. John had been worried about Sherlock and had not felt like dealing with the war memories as well. He had taken the necklace off, dropped it in his bedroom drawer, and promptly forgotten about it. In the wake of Sherlock's death the dog tags were the last thing on John's mind. When John was packing to move out of 221B he had found them missing. Surprised, he had searched the entire bedroom as well as the rest of the flat. He knew he had left them in his drawer, but now they were nowhere to be seen. He never found them and finally gave up, not wanting to linger in the empty flat.
Over time, John got used to the missing metal tags and started to let go of the war memories. They still haunted his sleep, although now it was usually Moriarty or Sherlock who stalked his dreams. Still, when distracted or frustrated-or simply out of habit-John would reach for the missing necklace and sigh.
Sherlock paced the room, lost deep in thought. He was worrying at the problem of James Lake, one of Moriarty's men. The man had gone to ground in Ireland and Sherlock was now trying to decide on the best avenue to ferret him out. As Sherlock paced, his hand unconsciously lifted to his neck and he pulled out the metal tags that were now warm from his skin. They were John's dog tags, of course.
The day before Sherlock met Moriarty on the roof of St. Bart's, Sherlock had a pretty good idea what possible outcomes could occur. He planned, of course, to survive, but there was always the option that his plan would backfire. Sherlock could not allow himself to consider other options, however. He had to turn all his analytical brainpower to surviving the upcoming encounter.
Sherlock did not allow himself to deal with silly emotions and feelings but he knew that if his plan worked, he would not see John again for a long time, if ever. With this thought in mind, while flying through the flat, Sherlock slipped into John's room and impulsively grabbed the tags. He later passed them on to Molly to hold for him. She was surprised—what need would Sherlock have for these?—but she knew better to question him.
When Sherlock moved in with Molly he took the tags back without comment. His soon formed a habit of wearing them when he was not out hunting criminals. When Sherlock did not want to risk wearing the necklace out he left it hidden in his room. Now, Irene bugged him about why he had dog tags, but he never answered. After a while she had learned to drop the matter, probably guessing whose they were.
Sherlock kept pacing the room, fidgeting with the necklace. The warm smooth metal helped focus his thoughts; he could concentrate on it rather than the worrying smell coming from the kitchen. Irene was baking a new recipe, much to Sherlock's chagrin. Frowning, Sherlock kept considering options for James Lake, worrying at the necklace all the while.
