Box of happiness

In the book, when the brothers are looking for happiness, they arrive at Biscuit Square. The square has an ant statue and is surrounded by different types of biscuits and candies.
There are two green and blue trees behind the square.

The trees are the gateways to the secret world.

The secret world contains strange creatures.

Decapitated immortal beings; Nine sisterly princesses who will live forever if they are virgins and die easily when they lose their virginity; The Golden Eyed Cat; Invasion of man-eating plants called anemones; A walking thorny grass... etc. are stories that are read in the secret world section.