Wallets were easily replaced.

Memories, were not.

They were so much harder to keep, as well.

So John ignored the amused glances he received whenever someone heard his ring-tone. He good-naturedly walked past the ignorant officers who thought the song funny. He hadn't realized when Sherlock had changed it, but now he felt ever so compelled to leave it be. In John's eyes, the ringtone was well worth worth a bit of teasing. It was probably the last thing he'd done to his phone, and he imagined Sherlock laughing at him.

Whenever he took out his old mobile, he tersely waited for the pitying looks to cease. This was special, it was the first thing, the only thing, Sherlock used to deduce him. It was proof he wasn't a fraud.

And so John endured everything—the pitying whispers, he accepted the saddened looks whenever his wallet was brought out. The slick leather frayed by age, but his friend's old bank card still in the first slot, unused. Because, for john, carrying that little bit of plastic, gave him a sense of normalcy he no longer possessed.

God forbid John Watson lost his wallet.