Hollow World

The "Otherworld" is the secondary setting of the story of Black Rock Shooter. It is only shown to be a large expanse of land covered by grotesque land features surrounded by an endless sea. Black Rock Shooter and other characters live in this realm, and the bizarre landscape is a witness to constant fighting between its denizens.

The true name for this realm is not yet disclosed, and to aid in reference, will be called "Otherworld".

From inside, it is composed of a variety of structures, with most buildings bearing a dilapidated, post-apocalyptic, and even desolate look in it. A striking feature of the structures erected in this realm is its dominant theme of checkered tiles in most of the floors and walls depicted.

Dead Master's Lair
It is a structure similar to a cathedral complex located in the middle of a large depression, surrounded with winding passageways from outside.