Scrolling through and I see a lot of people looking for an incest patch
Truth is, this game doesn't really need one. There are tons, and I mean tons of games where once the incest is taken away it just feels off (especially games like dreams of Desire or Man of the House where suddenly you're just living with two girls and your landlord) but this isn't one of them. Honestly if I didn't already know she was originally your cousin I wouldn't be able to tell you. Because seducing family may be common, but so is games trying to bang your new Roommate/Childhood friend (Hell in "similar threads" there's plenty of examples)
That being said, if you're really into incest (and more power to you) and you really can't enjoy the game without it then so be it, but I think this game holds up on its own without it. Just my 2 cents