What is the ruling on reading novels or illustrated stories about soul swapping, and is it permissible to watch or read anything related to spirits in general?

The transmigration of the soul from one body to another (reincarnation) is invalid, both rationally and Islamically. To affirm it is an act of disbelief that expels one from the fold of Islam. Knowledge of the essence of the soul is something God has kept for Himself, as He Almighty says: "And they ask you, [O Muhammad], about the soul. Say, 'The soul is of the affair of my Lord. And you have not been given of knowledge except a little.'" (Quran 17:85) Based on this, it is not permissible to read stories that include these disbelieving matters or invalid beliefs.