The Princess Has the Constitution of an Eagle Workshop

I found myself reincarnated in a game where, no matter which ending you reach, the final boss kills you in the end. "Has no one told you? When you lie, here and here tremble." I was sure my life was over But then But from now on, I wish this would turn into a secret affair. A late warning, but you shouldve been careful from the start. Once you give in to someone like me, theres no going back. Final Boss, why are you acting like this all of a sudden?!