Responses
I know right? It was pretty obvious.
no, I think it was a simple remark.. she may have been thinking till now "they are are close , it 's kind of unexpected... or maybe not, since they have been living together for so long".. But that's only after hearing Misaki speaking of Usagi all day long she started thinking that they may be "too" close and that it's supicious
Why is everyone acting like it's a huge shock that the sister-in-law knows? She was definitely suspicious already here: http://www.mangago.zone/read-manga/junjou_romantica/mf/manga/junjou_romantica/c083/pg-16/ and http://www.mangago.zone/read-manga/junjou_romantica/mf/manga/junjou_romantica/c083/pg-43/