Sleepwalker discovered that wise men drew a world map for After Dreams. So far, we know that there are four continents and one castle. Nederland is the southern-most tropical land where the party never stops. Alice Dream is a fresh and simple countryside. The Land of Oz is a frigid border area still in development and is connected with The Land of Oz and Match Girl's Paradise.
These four continents scattered on the Mirror Sea border Loyal Heart Castle. However, there are still many undiscovered territories on this map that await Sleepwalker to discover.