The old historian didn't notice I was following him, smothering a giggle behind both hands so I didn't give away my stealthy position, until he reached the door to his shop. He had the glass entry pulled partway open, catching my reflection behind him, before he turned to face me down with a scowl tinged with enough nervous anger he knew I'd caught him in flagrante graffiti delicto.

Before he could splutter out any kind of attempt at deflection, I poked him in his narrow ...