What kind of story did the ring tell? In the end, what was going on with Sadako's background?

The Ring of Midnight was a classic horror novel about a woman who heard a strange woman's scream in the middle of the night and found herself trapped in a strange building. Everything in the building made her feel extremely afraid. At the end of the story, she found out that the source of the scream was a Sadako. Sadako's background was a mystery. She was actually a cursed human who had been punished by the heavens for doing something immoral, causing her soul to be trapped in this building. In the story of the Ring, Sadako obtained the souls of humans through some strange methods and began to take revenge on humans. The story was very complicated, full of horror and strange elements that made the readers feel very scared and nervous.