Steam isn't going to chance their business with laws. This game is a form of beastality porn and loli, which is illegal in much of the United States, even even "free speech" involving it is also illegal.
So, while sex with actual animals is illegal, the game could be taken as promoting it by allowing you have characters do this. Valve isn't going to be cool with that so expect much of this game to excluded from what is in Steam and be more of what Fallen Doll was.
Now, with the loli content, yeah, that's not not going to be from the direct Steam release lol. There have been several recent charges against people having loli content in the United States.
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