Did you change the language before starting the game?
Viewing post in Lustful Sin v0.9.2 update! comments
No, i just started it, played for an hour or so and couldn't save when i tried. i played for a bit to see if it was just that part of the game bugged out but it wasn't. I also tried a new game and it was broken at the very start too.
Edit: I deleted it alongside the zip folder and tried a fully fresh install and now it seems to work