Ah, what's wrong with having a party once in a while? You're only young once, so why not? All that working with Avex must be pretty tiring once in a while, especially when you're in the middle of a concert tour in a different country.
As for the low cut dress and the bra, I don't see why the media has to make so much of a fuss. From that photo, all you can see are a few black lines. To further that, the photo was even taken from an elevated view of her, and you can still see very little. No big deal. Besides, in one of her fairly recent calendars she posed in a bikini, and even less in others. A bikini is for display whereas a bra is not, but personally I don't see much difference between the two. Obviously one is waterproof though. Please correct me if I am wrong though, I am a male and I don't know much about these things of course