After I died, my soul was reborn in another parallel world and possessed a patient who had died during a “paranormal investigation,” turning me into an “eerie being” posing a lethal threat to ordinary people. But I retained my reason and memories, and had to survive as an “outsider” in this world, where eerie beings were constantly returning and rules were strict. To earn a “stay of execution” that would let me keep living, and the “spiritual essence” that would make me stronger, I had to keep entering different “paranormal domains,” haunted houses in the real world, and completing tasks set by their rules as part of the trials. And every haunted house led to the director of the mental hospital where I had died, a mad scientist trying to explain and recreate “ghosts” through science.