It is very difficult for the code to follow what you do during the game and make the changes according to it. (Of course it can be done but then you need an expert programmer to work in your team.
Not to be rude but you are vastly overstating the complexity required to track if you changed variables within the game.
For example; Check to see if corruption is high enough, check to see current color state, change color if corruption is high and color state is not the changed value. Do nothing if you have false return on the conditional statement.
These body modifications are a pain in the *** for the developer. You need to do 2 different scenes for every part of the story because of Katie's hair
Well unless the color of the hair is mentioned in the text all you need to do is change the displayed picture. In the CG renderer you load the different body type preset and render the image for as many combinations as you can possibly have. If the hair color is mentioned you simply throw an check in the text to use the correct color text. You already need to select the right image, all this does is put a tiny amount of optional selection.
If might look something like:
ShowImage (if hair_color ==1 Party_sex001_Blonde.jpg, if hair_color ==2 Party_sex001_Brown.jpg, else return Error)
"Your (if hair_color== 1 'blonde', if hair_color== 2 'brown', else return Error) hair is around your shoulders."
(fake code used as an example)
Katie change her hair overnight and tattoos appear on her body.
You would either offer the change option to the player when it's conditions are met; Effectively just call the change hair color function. Or you might have locked out the option to change due to the progression of the game so you keep using your checks that shows the right image and text, as exampled above.
And now, there are people who wants the ability to choose the placement of the tattoos at these games. Can you imagine the result of this at the sex scenes?
With the correct image setup you even avoid the need to have duplicate renders by showing the tattoo as an overlay image. Then you just need the tattoos as a collection of images you can call to apply, saving on file size. This is a poplar method for many RPG Maker games. They have parts of the body in different images that get called to create a single presented image to the player while giving the artist vastly lower work load. Rather than needing to draw each possible combination they just draw each part once and they get placed onto the image.
These games are not being made by big studios and the devs are only making about 3.000$ from them. That is not enough to include every fantasy of every supporter to your game.
It's very basic programing to make it functional.
you need an expert programmer to work in your team
I really object to this statement. What we are talking about is the most basic of basic programing, end of week 1 in an introduction programing class.