why is the ghost presented in such a terrible light?

The Ghost is the protagonist of Oscar Wilde's story, "The Canterville Ghost". From the name itself it is evident that the the Ghost is a frightening scepter. However, his deeds when he was alive does not let us pity him. He had murdered his wife for being an incompetent housekeeper. Moreover, he did not even regret his deed. The Ghost also took joy in frightening the inhabitants of the Canterville Chase. The Ghost had viciously frightened people so much so that they became mad, ill or began suffering from nervous disorder. However, such description of the Ghost is essential to bring about the culmination of the tale. If the Ghost's character had not been frightening, then Virginia would not have been able to redeem his soul. Thus, to ensure peace and freedom to the Ghost, it is essential that he be presented as a terrible character initially. This also makes certain that the reader is able to pity him at the end of the story.