Joy is a former soldier, daughter of the Land Marine who was assassinated while on a mission. Joy was approached by a warrior, a close friend of her late father, to join the 'Project Busaba', a project to train tough girls to be assassins to serve the nation. She decided to join the project and passed the test, becoming an assassin under the code 'Busaba 029'. However, while she is doing missions, 'Busaba 029' finds suspicious things about her father and the project itself.

It all begins when Brick receives a mysterious package. Inside the box is "Anna," an artificial intelligence-programmed sex doll that can transform into a human being.