Mikage Kirio comes from a family of ninjas in Japan, who were forced to cease their operations after the Meiji Restoration. In today's world, the Kirio family runs the Shadow Village Company, which provides tailored security services to affluent and influential people. For a long time, Mikage has been working with a team of bodyguards catering to the needs of Mr. James G. Rod, a widower. Despite the disapproval, she harbors romantic feelings for him, and in turn, Mr. Rod finds solace in Mikage, reminiscing about his family. Mr. Rod proposes to adopt Mikage to give her the chance to lead a normal life free from danger and attend school.
Sadly, the next day after Mr. Rod's proposal, he experiences another assassination attempt. In the aftermath of the tragedy, Mikage struggles with whether or not to honor her master's final wish.
