When are we seeing Haruka again? I wanna have these two sisters meet in the presence of the MC. That's sure to be fun.
I'd like it if MC tells Shigure soon that she looks exactly like his gf and shows her a picture... this coquettish girl is flirting too much treating him like a typical single romcom protag, but maybe she'll treat him differently if she knew he had a gf... and that gf is her very own sister.
Then again I can see that not happening in this kind of manga for the sake of misunderstandings...