>>16750944
Re-L and Pino climbing a spiral staircase. Pino says "look, it's the egg!"
"The egg? Is that from one of your books?"
"Yeah. It contains all kinds of treasures, and children, and..."
It's important to note none of the books Pino (a cogito virus infected robot) are real. They're all blank until they're animated by the "proxy" she's connected to (Vincent Law / Ergo Proxy I assume, though it could be Monad or Proxy 1). Several scenes show their contents basiclly blowing away and leaving blank pages.

It was the throne room for "Monad" before it was "plundered" by Romdeau.