Not used to see Japanese clothes in real life. What's wrong with Souryuu's anyway ? The wrinkles ?
From what I can tell based on my understanding of how kimonos are supposed to be when worn properly (and from the general comments on Nico), Souryuu either has her obi too tight or doesn't have enough layering with the nagajuban (under-kimonos). Kimonos are meant to hide the figure of ladies, and Souryuu has hers on in a way that accents her breasts. Compare with Hiryuu here who would have a much flatter figure even when viewed from the side.
I'm less sure about loli Souryuu but I think young Hiryuu is saying that her dress is too thin/revealing and is asking her to cover up a bit with the shawl (is it a shawl?).
Hiryuu (28) and Hiryuu-chan going to the wedding reception