Maggie Hiraoka is a Japanese-American character who works as an idol journalist. She serves as the host of a popular information variety program titled Maggie's Show, which is broadcast from a lunar base.

Her journey into space begins when she visits the International Space Station, and she later travels aboard the Galileo, a cislunar transport spacecraft. Maggie possesses sharp observational skills, which she demonstrates by detecting a suspicious military robot on board the ISS. Her curiosity about everything around her, while a defining personal trait, sometimes leads her into dangerous situations. This tendency is most prominently illustrated during a lunar base bombing incident, where terrorists attempt to kill her. She is rescued at the very last moment by the protagonist, Gorou Saruwatari.

Following this life-saving event, Maggie's role in the story evolves significantly. She decides to use her influence and power as a member of the mass media to support Gorou in his endeavors. Her capabilities extend beyond journalism, as she becomes a crucial operator during critical mission events. When a massive field of debris cripples the space station, she operates a covert military robot known as the X-0 Guardian through a neural interface, using its abilities to help save the ISS crew. Her physical appearance is distinguished by her pigtails and a noticeable mole or birthmark.

Her interactions with Gorou Saruwatari create a significant personal connection that redirects focus from his previous relationship with another character, Riyoko Ikeuchi. Through these experiences, she transitions from a media figure whose segments could be seen as lighter entertainment into a serious and important participant in the central events of the lunar missions.