Chu Yue, the ace of the modern Z organization, was framed to death, and under the guidance of the system's Nine Desolation Mirror, his soul traveled to the Nine Desolation World, and under the system's mandatory tasks, he continued to practice and become stronger in order to survive. While performing system tasks and practicing adventures, Chu Yue discovered the shocking secrets hidden in the original owner of the body he was wearing. As Chu Yue unearthed more and more secrets about the original owner of the body, he unexpectedly discovered that he was not the only host of the Nine Desolation Mirror System, but there were other hosts of the Nine Desolation Mirror System in the Nine Desolation World.

In the late 19th century, as the cruel times of the Bakumatsu period came to a close, a new Meiji era marked the age of restoration for Japan. With the war over, its infamous hero Hitokiri Battousai disappeared into thin air, leaving only his legend behind. Years later, a seemingly plain wanderer named Kenshin Himura encounters Kaoru Kamiya, the owner of a struggling local dojo in Tokyo. Kaoru pursues a self-proclaimed Battousai who roams the streets, indiscriminately killing citizens and police officers. Furthermore, the warrior professes to use the Kamiya Kasshin-ryu—a sword style developed by Kaoru's father deeply rooted in the essence of life, not death. Kenshin decides to help Kaoru take down the impostor and restore her father's dojo. Unbeknownst to all, Kenshin is none other than the real warrior whose name still terrifies the people. Although Kaoru eventually learns the truth, his oath to atone for his murderous history by bloodlessly protecting the weak moves her, and she welcomes Kenshin to stay at her dojo. However, Kenshin's ideals are soon challenged by ghosts of the past and enemies of the present.