My god, she wore the China dress? That is the most awkward teenage thing I have ever read.
I knowwwwwwww. The first time I read that I was like, "oh, honey"--which is of course the all-purpose Southern US reaction to when someone has done something really dumb but nobody is brave enough to be blunt about how dumb they're being to their face.
Shimamura clearly has some thoughts coming into her head that she can't push to the side anymore, as evidenced by the scowl on her face when she got her thumb jammed thanks to Awkward Adachi. My concern though is that she's still manged to twist things enough... so that she's decided that she is going to be "onee-san", hence the head pats and the "you have to ask first, okay?" thing with the hand holding. Guess we'll see what's actually rattling around in that noggin in a couple weeks.