What was Pokemon world
Pokémon World was an area that was originally accessible from the Highway, but has since been completely removed in newer versions of Yume 2kki. The area was given this name because of its use of sprites from the Pokémon Game Boy Advance games.
Desu-chan and Onee-chan were found here, in early releases close to the area's entrance, and in later ones down an infinitely looping path that could only be bypassed with the penguin effect. Onee-chan sat on a bench holding a drink while Desu-chan would wander around. They are currently found in a rest area at the end of the southeast road of the Highway. One of the uboa-faced stars that were present in this area can also be found there.
The fairy that gives you the Fairy effect was also originally found here in a chaser-guarded area where you would have to catch it, but it has been imprisoned in a cage inside the Black Building in newer versions of the game.