Black Cat Question: What is the "fiend Intemperance" and how does it affect the story?

In Poe's short story, The Black Cat, Fiend Intemperance is referring to the narrator's alcoholism and because of the narrator's alcoholism it has caused him to do some pretty ghastly things. He took out one of his cats, Pluto's eye, because he was drunk. "...much intoxicated...I fancied that the cat avoided my presence. I seized him; when, in his fright at my violence, he inflicted a slight wound upon my hand with his teeth...I took...a pen-knife, opened it, grasped the poor beast by his throat, and deliberately cut on of its eyes from the socket!" (Poe 2). When he became sober, he realized what he had done and felt guilty for it. Years later after Pluto was long gone and the narrator and his wife moved somewhere else due to their house burning down, the narrator went back to the wreckage of his old home and found another cat like Pluto. It was even missing an eye. As time went on due to his alcoholism, he started to go mad and wanted to kill the cat. His wife, however, stopped him but this only made him angrier and he killed her too.