One of the best if not THE best hentai game I've played, but I would only rate it about 9.5/10.
My personal main gripe with it is the fact that pregnancy can only lead to an ending, and that there is no content regarding it after/other than the ending. No after-end scene, no visual changes before the ending happens, none of any of that.
I'm aware that "incest is bad"; and don't get me wrong, it is, but having it happen ONCE in a family tree will most likely not lead to your following family being made up of mutants.
Other than that:
1. I wish some parts of the game were better explained. Lots of pretty important gameplay details just aren't explained at all, so heavy experimentation or just looking up answers feels necessary.
2. The game has lots of RNG elements, which is both a good and a bad thing in my opinion. This feels like a very intentional part of the game, so I can't complain much, but it makes learning the game a bit of a rough experience with so many things being able to fuck you over.
About the things I like about the game... it would be almost everything else, so those would be too many to list. The thing I like most I think would be the the ways that you go about... corrupting your imouto, so to say. Getting her to listen to your requests, then getting her to enjoy fulfilling them, then getting her to even ask you for certain things at certain points as well. It feels like a pretty natural progression and gets you more invested into the game and your imouto.
What I used to play the game was 妹prpr's translation revision version, as well as Daeson's Color Mod. These two, but especially Daseson's Color Mod, made my experience of the game 3 times as enjoyable as it would've been without their additions to the game, so I would like to thank them from the bottom of my heart <3