Another name for this bird is Java Rice Bird, as it does comes from Java (and Bali) and lives in the rice fields. They are also found in grasslands, meadows and urban areas.
While native to far realms of the world, it can now be found everywhere, as it has been favorite cage bird, which of course escapes into the wilds. In the USA, they are found in Hawaii.
This bird is another example of those estrildid finches (remember that word from the African Silverbill?) and while seemingly small, it may be the largest species in the estrildid family.
It is known to be a gregarious bird, usually in flocks, but what I am seeing here now, is mating season, hence many birds in pairs.
These birds have appeared in Chinese art from Ming Dynasty and 17th Century Japan. Unfortunately, they have been considered an agriculture pest due to rice cultivation in far east, so have been hunted and eradicated and are now considered a critically endangered species, with about 10,000 left. I was most fortunate to see them again!
Japanese print- Hokusai (1760-1849)