Hello again. Yes, visual novels and interactive novels usually offer the option of returning to the previous sentence/text/paragraph (usually with the mouse wheel). It is not mandatory of course (especially if it is difficult to implement), but it offers a better reading comfort. As an avid visual novel reader I can tell I use this option quite often. We use it for exemple to check information or details given earlier in the story, etc.
BTW I really looove the art, did you made it? It has some Otto Dix's vibes, it's beautiful and disturbing at the same time. This is perfect for this kind of story. It was as if the characters and the world were distorted through the eyes of the disurbed protagonist.
Sorry if my english is a bit awkward, but it's not my first langage^^