In my mind this is the most japanese game of all.
I don't even know how anybody came out with this idea, but somehow, magically, it works. The game is a lot of fun, and while it is very short, you can still go back and play old levels, which never get old. I've got to admit that I really struggled at first to control the katamari, and I never really learned how to do it properly (if there's even a proper way to control it), but despite that, things never got frustrating, and you always feel you're getting better as you play, even more than in other games.
I really like the music and absolutely love the main theme, and the whole aesthetic.
This strange little game is a real gem, and I will surely go back playing it from time to time.