I'd rather not get the Gainaxing.
And even if she didn't wear a bra, which she doesn't, if her previous "too sexy" back change said anything, her outfit, the darker part, resembles a corset (key word: resembles. I doubt it's a real one, but there are certain copies that work the same way, and allows you flexibility), and perhaps acts like one, and would be able to hold it in place.
Now, this topic would have made more sense if you posted it when they had that piece of shit string behind to hold the outfit together.
Her chest size is of the female average anyway: not too small or too big. Just balanced, and right. CGI, side views, and recent scans do not lie. The bonus is that the clothes she wears accentuates, outlines, and makes the shape of the breasts more obvious, but it's not any bigger, really.