Those buttons always take you to the next/prev image by the posted date, not the model name. This is indeed a coding thing because in order for it to work like you'd expect, the page would have to tell how you sorted the image index page you came from; for example, if you came from a search result for X, then "next" should go to the next picture of X; or if you sorted by high score, then "next" should go to the image with the next highest score, etc., for arbitrary combinations of these. I haven't found a good way to do this.
Pretty annoying when your in the moment and get some randon picture. Not the one with the correct name.
Is it a website coding thing?