The title is entirely accurate as to the form of the piece, through which device gradually unfolds a history of great delicacy and beauty, which evokes an almost Dunsanian elegiac whimsy. I do not wish to spoil the story by offering specifics, but there are images which will stay with me.
This Plague of Dreaming is not affiliated with either Catherynne Valente or Clarkesworld Magazine, and offers this link simply as a free show of admiration for a wonderful story.