Unfortunately, I don't think that's the issue. I'm running the extracted version of the game. I've been playing for about 10 days now, and I've never encountered any bugs in this amazing game before.
The bug only appears in my last 3 .save files; my older saves don't have this problem. That's why I'm starting to suspect that the issue might be related to Ren'Py rather than the game itself.
Thanks for the suggestion, Great Deimus 🫡