delete your save folder
\AppData\Local\TheLustland
and \TheLustlandAdventure
You only need to delete the two save files in the save folder "QuickSave_32.sav" and "SaveMetadata.sav".
Deleting the rest also deletes your character creation data which isn't a problem. Unless you want to remake your character every time it happens. I believe the metadata file is the culprit, but if you just delete that one then all items in the game are gone including your clothes and NPC clothes. Meaning that everyone is naked. Among other things I have not yet noticed. But that is a quest breaker unless you already finished the quest. Regardless, I wouldn't delete the entire folder, just these two files.
Also, if you spawn the 3 girls in the map and save the game then that save likely will be corrupt. Play with the girls, then dismiss them before you save and it should be fine. Other things may corrupt it, but it won't be the girls which for me corrupts it every time I forget to dismiss them.
Edit: Hmmm, I just tried v33 for the first time and it seems there is an autosave feature now. I purposefully did not make a save and closed the game with 3 girls spawned in, but when I went back in to start over there was an option to continue. It put me right in front of Draginel where I was when I closed the game, but after continuing the girls were gone. So maybe that part of it was fixed, not sure without further testing.