The incest patch changes Allison to your grandmother, making Liz and Amy your aunts, and Cat your cousin.
Also,
here is the link to
FatGiant 's info on the various parts. Since we'll soon be starting part 4, let me put in a quick description of how things work (which will do no good, as the people who will ask are incapable of using search to find posts made before theirs):
Moonbox breaks the game up into 5 GB chunks; this makes life easier for people downloading the game, as some download methods have difficulty allowing downloads larger than that.
Each part behaves as a separate game and must be downloaded into a separate folder. The only way the various parts interact is by taking a special save made in the previous version, and using it to seed the new version (remembering which ladies you've chosen to interact with, your name for the MC, and so on).
TO GET THAT SPECIAL SAVE you
must save on the page at the end of each part that tells you to save on it. This is different from the page at the end of each release, which tells you to
back up a page or to and save. Those pages have a picture with Allison (and Cat, maybe? Havent seen one in a while as I like to make sure I've always got some to play). The end of part pages have a plain black background with text. If you haven't seen it yet, keep playing the part you're on until you do.
Once you have that save, switch to the next part's folder and launch that part. It should just start, without any problems. See FatGiant's more detailed write-up if necessary.
Note: the Android version works much as described, except that the apk for each part will install over the previous part, so the info about folders is not relevant. All the info about needing the final save for the previous part does still hold true.
Good luck, and have fun.