A brief story:
Once upon a time there was a very pretty apartment where the rooms had walls, but no ceilings. You could hear everything happening in any room in any of the other rooms because there were no ceilings. Even when the door was shut, you could hear the sounds others made in other rooms. Even in the bathroom.
This very pretty apartment was in Mexico City. Sometimes, when people travel to Mexico from other places, the water there makes them very sick. They have to use the bathroom a lot, and make funny sounds (and sometime smells,,too) when they are in the bathroom.
In this apartment, the funny sounds and smells don't stay in the bathroom - everyone gets to experience them!
The end.