I really though this was going to be the typical story with incest and lots of sex but then I read the comments and it's really not.
I'm glad they are happy and comfortable with each other; but i really didn't like how they manage their problems, of course they talked about it and understood each other, but it would be much better if they went to therapy because what happened in the past it's a serious problem. The author didn't dig on the past so I can't say it was really based on it, meaning this is a story totally based on their relationship, with a lot of sadness and happiness.
Koko Wa Yasashii Niwa