Hanging the other way. The column does not move — that is the part worth checking on a page that uses several of these, because a reader scrolling past a run of them should never feel the text drifting left and right underneath them.
What moves is the picture, and only ever outward: the measure it leaves behind is the same measure the paragraph above it had.
Filler so the stage behaves like a page — something to scroll, and something for a translucent bar to pass over. The component above is the subject; this is only the ground it stands on.