Can somebody tell me How to I update the game without losing any progress? I don't wanna lose all of my progress when I download the new version '). (Edit- I am on Android btw.)
If you are playing the Windows version of the game:
Your save files are located here:
C:\Users\xxx\AppData\Roaming\RenPy\IsekaiBrothel-Saves
xxx corresponds to your Windows username.
Save files have a .save extension.
For example: 1-1-LT1.save
To update the game, delete the old version of the game.
Download the new version.
Unzip the new version.
Launch the game.
Load your latest save file from within the game, and play.
If everything works correctly, you can empty the Windows Recycle Bin.