If you are playing through the Itch.io desktop app, underneath where it says "Launch" for DDLC, it should say "Show Local Files". Click on this button, then the file "DDLC-1.1.1-pc". The files should all be there, including the "Character" and "Game" files. See the images below. If you don't have the desktop app, I'm not sure how to open the files, but the desktop app is free and easy to install, so that's an option :).
Go into your library of games on steam, you will see the game Doki Doki Literature club and once you see it right click it with your mouse, Once you right click it you will left click at the bottom where it says "Properties" once you do that click on the top all the way to the right where it says local files, Once you do that it will give you options, You will click "Browse Local Files" and once you do that it will bring you to Files with the DDLC game.
