Hide and Seek creates a Nen space of twenty-one rooms, on four floors. Each room is isolated. The entrance shuts when anyone enters, so to return to the real world, one must exit by a different door.
It is possible to create multiple entrances. The number of possible entrances differs depending on the size of the room. The exit leads back to the portal used for entry. So, as a general rule, one can only enter and exit via the location of the entry portal. However, using Knov’s master key, an exit can be linked to any portal.