In Star Century Zero-One-Sixty-Five the Global Union was founded to serve as the ruling and governing body of its numerous member planets. In order to supervise the vast amount of interstellar commerce between the planets, the Galactic Organization of Trade and Tariffs, or G.O.T.T., was simultaneously born. Its initial purpose was to provide an impartial mediator to the various planetary governments of the G.U., primarily in such matters as trade imbalances and treaty disputes. In order to ensure the best interests of its clients, the G.O.T.T. employs its own law enforcement officers: The ES Force. Each member of the ES Force has been granted his or her own unique power and ability. Working in pairs, these cosmic sentinels ensure that the fair trade laws are upheld and that all treaties are obeyed. Without the skill and grace of the ES Force, criminal organizations would bleed the galaxy of its precious economic resources. Sworn to uphold all that is right, ES Force members Eclair and Lumiere patrol the stars bringing evildoers to justice. Along the way the two young heroes learn much about the true nature of those in power...and about themselves.

In the future mankind will venture to the far reaches of the cosmos using technologically advanced trains, perhaps the least likely method of intergalactic travel. The fleet of the Galaxy Railways transports countless galactic citizens from one exotic planet to the next, protected by the SDF, the elite force protecting the Railways Fleet against terrorists, meteor storms, and malicious alien life. Manabu Yuuki dreamed of joining the SDF like his father and brother before him. His mother, desperate not to lose her whole family to the infinite void of space does what she can to derail his dreams, but Manabu is too much like his father, too stubborn to go back on his word. He boards the train to Destiny Station, where his own destiny has already begun.