She used to make a living by killing people, but she fell in love with him by chance. However, this relationship was destined to be a tragedy, and the person she loved most was killed by her sister. She sealed her sister with her own hands, but couldn't bring herself to kill her. . . Hundreds of years later, she met her sister in the time and space of the end of the world, and unexpectedly met his reincarnation. Hundreds of years later, where will her love affair with him end?