Possessed by a Transformation Heroine: Blue Saintess Saffir, Miyuki Mei SPSF-76

Satsuki, a girl with a strong sense of justice and true self, encounters the resurrected evil god Dagon while patrolling the student council with her classmate Hikari. Satsuki is attacked by Dagon and his Deep Ones and loses consciousness, but encounters the saintess Sapphire in her spiritual world. Satsuki is a descendant of Sapphire and is asked to lend her body to Sapphire to defeat Dagon. Although confused, Satsuki decides to fight alongside Sapphire for the sake of justice. Sapphire, using Satsuki's body, battles Dagon. While dispelling the Deep Ones, she almost allows Dagon to escape. At this moment, Dagon possesses Hikari's body… [Bad Ending]