It was a movie which sampled as well. There were lots of little details of exactly the sort a stranger particularly notices in Japan - people reading graphic graphic novels on the subways, for example; tying prayers to tree limbs. The movie didn't explain - it didn't need to. If you didn't understand, it would only add to the ambiance it evoked.
The only sequences I am less sure about are those with Charlotte's friends - they were confusing - but to a degree I know they were meant to be so. Also, their pacing seemed less sure than the rest of the movie. The karaoke scene dragged a little, I thought.
Also - I loved the dinosaur and elephants walking across the building!