The concept is isolated life from the world and separation from society.
An inhabitant can travel alone.
This sphere is able to go any place that has gravity and it can roll down a mountain.
The sphere has passages in every direction. The inhabitant uses the passages to move the sphere to another position from inside.
Interior has six functions: running, eating, sleeping, resting, thinking, and rolling.
The space for rolling has a function to defend the inhabitant from a shock when the sphere rolls down a mountain.
