(Alex, feel free to move this if you don't think this belongs in GD)

In Diamond and Pearl, the Pokemon Mansion has two doors guarded at all times by maids. So, I ask you this: what are your crazy ideas about what's behind the doors?

Personally, I think there's large bill piles much like Scrooge McDuck's money pile proving that he's not really that rich. Hiding from the Pokemon World's equivalent of the IRS, maybe?