Alex, Pedro, and many of the characters live in Pangilan, one of the provinces. More info here
Alex and Pedro's world is still on Earth. Therefore, asking them where Japan or the United States is is possible. Because of that, food such as sushi or pizza is known.
Alex and Pedro live in Pangilan City, Pangilan known to be the melting pot of, not only to the country, but to the world, like New York City. Not only are there people from all over the world in the city, but also animals from all over the world.
The dialogue is in English. However, people can only understand themselves. Similarly, animals can only understand themselves. If both a person and an animal are togther, if one of them talks, the other usually cannot understand each other.