well, indivi actually already told you where to find your saves. in "read me" txt file.
"File Locations
Save and config files are located here:
Windows: C:\users\(username)\AppData\Local\UserData\Default\Lust Doll Plus
Mac: \Users\(username)\Library\Application Support\Default\Lust Doll Plus
Linux: \Users\(username)\.config\KADOKAWA\RPGMV\Default\Lust Doll Plus
(May need to sudo nautilus if you don't have access to .config)
Android: \data\data\indivi.indivigames.lustdollplus
(Requires root access)"
so even by completely deleting game you won't delete game saves if that's what worries you :)