On his journey to the "Other Side" Reader (and his "natural companion" Writer) meets various Ghosts and Demons, Holy Spirits and Gods. He also meets Singer, who is neither Ghost, nor Demon. At some point she becomes important to Reader. Realizing this won't stop him though.
The world of Ghostdream should be scary, but it is not - it is just dark. The story should be sad since all the characters are more or less dead, but it is not, because they normally remember nothing, except some minor detail or two (for example the protagonist remembers himself reading a book - this is why they call him Reader. It is his only memory after all).
Ghostdream is a retro-style Point and Click Adventure game with puzzles, exploration and story.