For images depicting characters without ofuda who normally wear one, especially jiangshi like Miyako_yoshika or Lei_lei.

Using -ofuda in the search doesn't work if ofuda are still present elsewhere, see post #1155593 for an example.

How about using an ofuda_on_forehead (or hat, or face) tag for both jiangshi and things like
post #479057, post #408820, post #420340?

ofuda_removed sounds like hat_removed as in the ofuda must still be visible in the image.

Well, we could use ofuda_removed for still visible and no_ofuda for completely absent ofuda.

Using ofuda_on_forehead is possible, but basically every jiangshi image would have to be tagged with it, we're talking about hundreds of pictures here. Still would be nice to have if other characters wear one, though.