And wow, I just made all of this for a game that does not give a lot of information, kind of like this freedom given by the developers.
I can relate to this somewhat, in the past I thought up a lot of lore for how the the health system could have worked in the first game, these thoughts were spurred by the Animal Farm level, whenever you reach your sword in the pig chase Rabiane's sprite immediately turned back to the normal sized sprite, in reality this was probably simply saving resources since this extremely specific scenario doesn't need its own unique sprites, but it still prompted me to think about how maybe the Sword worked with like some sort of trinket on her person that purified her body from abnormal effects and generates a magical shield or something.
Then I realized that I was thinking about this maybe a bit too hard and that none of these conclusions were probably even intended by the developer, so I stopped, in hindsight this was a poor excuse to stop the theorizing since it was pretty fun.
Anyway, this theory is probably a Debunked, since I recently tested in the Animal Farm level, and discovered that Rabiane's level of swelling isn't reset once she escapes, when you get the sword, break the door and get back to the normal start of the room;
Getting caught again simply continues the scenes from where you last left off, you don't start all over from the start with her normal sized breasts.