The level itself is a large black platform with Anatat Tatanatat's skybox. Also on the platform are Chang, Mai, Roofus and Winnie. They will be replaying their motions from their cutscene after you rescue them in Saving Winnie and Mai. They cannot be hurt, and you cannot interact with them due to there being no collision data applied to them.
There is absolutely nothing else in the level, not even music or additional sound effects, and falling off to fluff yourself will give you the option to restart or exit the game.
Should you be playing Pool Test, selecting 'return to hub' will lead you back here.