It's alright, I can totally land this!
This area operates in a similar way to Flying Fish World and Concrete World, in that it is comprised of elevators which take you to completely different areas on the map, however this world has a different transitional effect when you go through the door.
Most of the doorways will lead you to dead ends, but Urotsuki can leap off some of the edges of the blocks in this area by pressing the interact key while facing them. Urotsuki will not jump if the Plaster Cast effect is equipped. You can jump up the blocks by using the Spring effect.
On top of one of the longer blocks, above the one leading to the giant, is an orange, ghost-like creature that will take you to the River Road. Also, you can find a flashing creature, which work like a portal to the Neon City.
Interacting with the pink-haired helmet girl will take you to Flying Fish World. Interacting with the floating ghostly helmet girls will teleport you to another part of the map.
If you head straight to the left after going through the doorway next to the Theatre World's entrance, you will transition to a long pathway where the screen will be zoomed out. When you reach the end, the camera will continue to pan left to reveal a gray giant. After viewing this event, Urotsuki wakes up.