I just wanted to say that whoever localized 'whisker biscuit' is a hilarious motherfucker. I never expected to see archery slang in a manga about a girl bullying her nub to draw things.
Doesn't quite count as wincest but I'll take it. Now we just need a ménage à trois for the sisters and the male MC. Better still, show us their mother and have an oyako-don.