Following text has been copied from the .flow wiki's page Blood Maze.
The Blood Maze (血液, aka the "Bone Maze") is a black world with blood trails and bloody bone like objects protruding from the ground in various parts.
This world is a connecting area. By going downstairs in the large blood puddle, the player will come to the White Room. Going through the door that resembles an open mouth, with blood dripping from the teeth, will teleport the player to the Insides but this is one way route.
The Candle World Kaibutsu also is found here.
You can enter the Red Body by entering the mouth-like doorway as a one way route.
DirectionsEditNexus>Neon World> Red and Blue path>Hospital (go up)
- The music here is the same theme as Hell.