Girl was sitting as a model for artist, charcoal drawing I guess. Artist was drawing, girl was chatting and laughing with her friends and the rest of the crowd was looking the scene. Common sight in any European city popular with tourists. No need to stop there.

But as I was walking by I noticed a crack in the wall of backs, model sitting just in the middle. Raised the camera, girl raised her eyes, noticed me. She shot the smile, I shot the pic.