Because of the internet, I can’t make anymore an inbreeding joke I had in mind, but, still, let’s say that incest runs strong in some family lines 
We’re with the daughter and son of a brother-sister couple, and the children are already happily breeding the next generation, they have a one-year old son, and work every day to still increase the family’s size, at home or during an onsen stay, with the blessing of their parents ┐(￣ヮ￣)┌
The drawings reminded me of a beginner Shunjou Shuusuke, somehow, it wasn’t bad, I’d say. See for yourselves, and thanks to Hardcase8translates! 
A precision: the manga is 63 pictures long, but in fact, you can divide it by 2, for a real, significant length.
There are 2 versions, first a “normal” one, and then another one with exactly the same drawings and dialogues, save one addition: the brother cums freaking buckets on his sister, let’s call it the bukkake version? （╹◡╹）
