The smile in her eyes somehow struck him as sad, even fleeting in its attempt at mirth.

As she spoke, it disappeared altogether and an almost sombre expression came into her face.
"Thanks.

I'll--wait," he said, suddenly embarrassed.

She turned to the window, resuming the wistful, preoccupied gaze down the avenue.

He made pretence of inspecting the wares on the opposite wall, but covertly watched her out of the corner of his eye.