Those character are from one of my series call Train42, it is About a large-scale space station called Pastobia, the space station has many unimaginably large and complex cities, industrial areas, life-support systems, power plants and other places, where it was originally a different alien civilization between the galaxy. The trade gathering point, after thousands of years of countless interstellar merchant ships and materials transported by other space stations, has made it expand to the size of a planet and has its own gravity. The story is about an alien boy dream about traveling around the whole of Pastobia, exploring various areas built by other races (including humans), in order to realize this dream he left his hometown as an adult with the best robot friend of his life and became a delivery of train 42 Crew on an adventure through a variety of stunning areas of the space station.(most of it is translated by google I not very good at English )