In a world where humanoid armored weapons known as "Titatonostrider" ("TS" for short) are used in warfare, troops from various countries converge on the island of Oahu, Hawaii, including Ao Isami of the Japan Ground Self-Defense Force and Lewis Smith of the United States Marine Corps. Isami and Smith cross paths during battle, but suddenly, their teams are attacked by an unknown enemy, scattering soldiers and sending their forces into disarray. In order to save their friends and survive on the deadly battlefield, they must fight with every ounce of courage and pride that they can muster.

Comet (12 years old in human years) is the princess of the Harmonica Star country and was to meet the prince of the Tambourine Star country at a ball where he'd pick a bride. But he isn't there and so Comet is sent to Earth to find him. He'll be known by the starlight in his eyes. She finds the Earth and she loves the people she meets there. Meanwhile, Princess Meteor of the Castanet Star country also arrives on Earth in search of the prince. Comet's companion is a little puppy with a star at the end of his tail named Rubba Ball. Of course, Comet was not the first to visit the Earth and love it, another before her did as well and married. Her pet (a white cat with bunny ears and a tiny heart on her tail named Bunny) continued life as a kind of fairy in the forest. Comet's power is drawn from the stars of her home and is channeled through her baton; she also wears a special pendant from where Rubba Ball immerges, and with which she can detect and find the prince.

In the distant future, mankind has colonized other planets in the universe. While many planets lived in peace, the planet Jerra has been ravaged by decades of war. Geist is an M.D.S. (Most Dangerous Soldier), an enhanced human with unsurpassed combat capabilities and an insatiable lust for battle. Because of his uncontrollable nature, Geist is cryogenically frozen and locked in a satellite. Several years later, the satellite crashes and Geist wakes up from his sleep to engage in another war. This time, to help the army stop the planet's central computer from activating a doomsday device that will lead to total annihilation of all life on Jerra.

In a world where humans coexist with androids called Neans, a group known as the Immortal Nine rises up against society. Tasked with disposing of the revolters, a Nean named Rouge Redstar (aka Metal Rouge) and investigator Naomi Orthmann head to Mars to track them down…but first, Rouge wants some chocolate.