The random violin music was one of the things John missed after his best friend decided to leave him. He missed dozens of things, many of which he hated while he was still with him.

But the violin was different.

When Sherlock played it, it gave him an odd feeling, a feeling of peace and stability that he never really had in his life before. The music was theirs, and no one else could truly understand what it meant to them.

It spoke of love and loss and thought. It was a welcome home. It was an apology. It was their own private communication. It spoke so much to the both of them and in so many ways.

John hadn't heard it in so long. He missed it. Sometimes he heard snatches of a long since played tune, but then they would disappear into nothing but pain and loneliness, like many memories of Sherlock did. They would play in his mind for an instant before crashing down hard with the weight of reality and breaking his heart all over again.

A year after Sherlock left him-left, not died, not committed suicide- John limped into the same old flat he'd had for years now.

Then he heard the music. His music. Sherlock's violin music.

The cane and groceries remained forgotten at the door while John rushed up the stairs into 221B.

The music was exactly as he remembered it, beautiful and haunting. This particular piece spoke of sorrow and joy and forgiveness and reunions.

John thought Sherlock was back.

I knew he wasn't dead! He wouldn't leave me here. He could never do that. He always comes back for me, and he's doing it right now.

The music seemed to crescendo as the door burst open with John's eager yet disbelieving face following quickly behind.

As it burst open into the empty room.

The imagined music vanished instantly, along with all of John's hope.

Sherlock was not back. He would not be coming back.

Which left John alone, yet again.