well, in this one the problem is worse, I mean even the normal scenes are in black and characters are invisible even the main character so can't see where he is in map.
After the character two all the hot scenes are in black, only in the prologue is when you can see the Vespa girl getting D, maybe is a Godot bug or a bad interaction with itch.io. I played some of your older games and I didn't got any issue, anyway I think your art style is great.