She's got a psychopath coming for her head, she's got a demon as a partner, and her cat isn't even a cat. This is her last life, and if it ends, everybody's doomed.
Living in a sorrow, regret and blame. She always feels like that's how her life will always be. But then he came, making life at least bearable. And just when she thought she could get rid of all the sufferings, little did she know that she's been dancing with the devil all along.