*doesn't notice Snape as he enters the shop -- when Sirius is preoccupied with something, the rest of the world fades into the background* *heads to the back catalogue area and asks for what he wants, smiling nicely when the staff member looks uncertain and politely asking if they wouldn't mind checking, just to be sure, and yes, they did already tell him they don't stock that series and no, he isn't with the Ministry* *is told it might take a little while, and is given a cup of coffee to keep him company while he waits*
*recognises Snape side-on before he turns away, and is about to say hello, but then remembers the name on Snape's business card and isn't sure what name to use to greet him* *walking over and tapping him on the shoulder probably isn't a good idea either, based on nothing more than their most recent interactions* *mentally shrugs, brushes the dust off a step ladder and settles in to wait*