In search of the fabled Mapman from the Nomad Star tribe, Lipumira tracks him down in Tokyo and discovers that the last survivor is a man named Gen Tokishima. Gen is the only one who can procure a portion of the hidden starmap that lies within the Earth. Upon obtaining the fragment, Gen faces a difficult choice: accompany Lipumira on her reckless quest to locate the remaining starmap pieces or stay on Earth. Eventually, Gen decides to join Lipumira, but he soon finds that his girlfriend has already commandeered the spaceship and wishes to accompany them. As Gen delves deeper into the truth of the starmap, he discovers that Lipumira's sisters are plotting to sabotage her efforts and will stop at nothing to do so.