I can see it now... Haley is the MC's best friend and next door neighbor, but nothing remotely sexual has ever happened between them. So they apply to work with the same company, and decide to move in together to save save money. Now, thrown together, and already friends, they start to gain other feelings for each other.
Now, how long do you think it would take to program that, and then go through the story's text to make optional all references to brother or sister or twin. Hell, I could do that in a few hours, and I've never coded a line of Python or Ren'Py. [Whether it would work or not, might be an issue.
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