I Turned the Tyrant Into an Obsessive Man

I was reincarnated as an extra princess destined to die at the hands of the soon-to-be-tyrant prince. I’d resigned myself to my fate, but he refuses to kill me. And now that I’m not dying, I find I want to live. But there’s something strange, a charged tension, between the prince and the duke. Could it be that my survival has somehow changed the genre of this story?