Trying to rack my brain looking for an older work. Details are fuzzy, but it is one where a guy/girl friend pair who are aware that the universe actively trying to pair them up sexually/romantically, which they are trying to avoid. There was one panel where they are shown slipping/falling in such an elaborate way that they end up in a sexual position. A diagram of the fall is shown. They exclaim that that should have been impossible. Eventually they give in since it is literally the universe trying to push them into a relationship.