Shattered Time: Rewind

Upon learning about the passing of his classmate, Natsuki, MC performs a ritual and is sent back in time to uncover the truth about her death. All the while, he has to come to terms with his own feelings and face the ghosts of his past. In performing the ritual, he also has to follow the rules set out by Terankos, an evil being of unimaginable power, or risk meeting with a terrible fate.