You’re haunting me.
A ghost is a memory half remembered, half forgotten. It drifts in and out through the windows, whether they have glass or not. You might mistake it for a curtain if you were careless. But other times, you’ll see it out of the corner of your eye and jump, shivering, then go back to shuffling the papers on your desk a minute and a half later. Ghosts waver in and out of focus like dust in the sunbeams.