The article also discusses the negative spiritual effects of yoga and reiki, but I will only include here excerpts about the two authors.

Link:
https://spiritdailyblog.com/spiritual-warfare/what-exorcists-say-about-yoga-potter

Excerpts:
Concerning J.K. Rowling and the Harry Potter books:
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“Exorcists have tended to conclude very harshly on the goodness of the story and the soundness of allowing young people to read it,” writes Fraune. “In his lectures, Father Ripperger provides important details about the creation and propagation of the occultic fiction books under the title Harry Potter. According to Father Ripperger, J. K. Rowling, the author, went to witch school before writing the Potter series. She wrote the entire series through autowrite, or ‘automatic writing,’ which is a technique involving demonic assistance. The spells used in the stories are real, as revealed by priests and witches themselves. Exorcists have told him that sixty percent of the names in the books are the actual names of demons exorcists have cast out of people.” (We haven’t been able to verify the automatic writing claim as yet. -Spirit Daily Blog)

One exorcist had to conduct exorcisms on three children due to their Potter exposure. Ripperger says one possession case involved five demons who claimed they had inspired Rowlings to write the incredibly bestselling (650 million copies) books.

Father Amorth was once quoted as saying, “You start out with Harry Potter, who comes across as a likable wizard, but you end up with the devil. There is no doubt that the signature of the Prince of Darkness is clearly within these books.” (The movies, watered down, are not seen as quite as detrimental but can lead to reading the books, claimed Farther Amorth; we would strongly advise against the movies as well.)
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Concerning Steven King:
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When it comes to “autowrite,” the author Stephen King also comes to mind. He has described a process whereby he simply sits at a typewriter with rock music blaring and lets the books flow from his fingers. In turn he has inspired at least thirteen rock, punk, or heavy-metal songs. His love for the likes of demonic bands such as AC/DC, Metallica, and Anthrax is reflected in the use of their lyrics in some of his books. He even bought a local radio station to play his favorite songs as he writes.
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