Reborn as the Doomed Prince

I died and woke up with the memories of my past life. I was the stepbrother of the protagonist in a book, a character who was constantly pushed around and made the protagonist's life a living hell. Why...? Why did my past life memories have to return after the incident where he was demoted to a slave? I wish I had regained my memories a little earlier, but it was unavoidable, and because I didn't want the world and the protagonist I loved to be ruined because of me, I decided to prevent Soo's misfortune. Introduction to the Work: *Genre: Fantasy, *Keywords: MultipleGong/OneSeme, Fantasy, Possession, Non-Human Beings, Omegaverse, Terminally Ill *Gong/Seme: 1. Chase Renhouse The prota...