One day, a brother and sister pair came to visit an observatory. The brother, Shota Tsukishima was a 20-year-old without a job and was there in order to be interviewed for a position as temporary worker. Hikari Tsukishima, his sister came along for the interview with her brother and also for a tour of the observatory.
While leaving the building was attacked by an invading monster from outer space. At that time, Shota was wrapped in pink light. From the light Shota heared a girl's voice saying "Please lend me your body" but the being of light noticed that Shota was a man, and it instead merged with his sister to defeat the monster.
- Akari Tsukishima: Junior high school sophomore. Dubbed a "space geek". She is the host to Jeanne.
- Syouta Tsukishima: A 20-year-old. After graduating from high school, he has been on a job search, but has been denied by 30 companies in a row.
- Jeanne: A member of the Space Garrison Force who came to Earth for training from the "Land of light" (A.K.A. M-78 Nebula). She is in fact an apprentice from training school and also happens to be a clunker.
- Kisaragi Yuki/Amur: A member of the Space Garrison Force in charge of global security. The self proclaimed "little sister of Zoffy", she was dispatched to Earth on the orders of Zoffy to be the immediate supervisor of Jeanne. Unlike Akari, Yuki is the result of Amur mimicing a human form. She usually works as an active member of the Earth Defense organization BURK.
- Amur's human form bears the same name as a character from Ultraseven Evolution's Ultra Garrison.
- Miya Tachibana: When Syouta was in 5th grade, Miya was a transfer student in the same class for a short period of time. She suddenly appeared in front of Syouta as an official member of BURK. She is really the Higher-Dimensional Life form Alien Ihaton, who stole the real Miya's identity. The real Miya died two years ago in a car accident.
- Sanae Kuroda: Akari's Homeroom Teacher. A well respected 20 year old. She is really possesed by Alien Campenalla as she targets Akari.
- Primitive Space Life-Form Guranbon: An irregular organism that absorbs both organic and inorganic materials. It was at the observatory where it became an octopus like monster from absorbing plants hanging from the ceiling.
- Mimicry Majin Alien Campenalla: A reptillian alien figure that tried to steal the Jeanne Spark by controlling Hikari's homeroom teacher
- Dark Machine Beast Gauche Don: A mechanical monster sent by Alien Porano. Appears in Shota's dream.
- Ultra Science Phantom Alien Porano: Sent Gauche Don, they only appeared in Shota's dream.
- Rock Bird Jobandon: A monster with demonic wings and a sharp beak. Its weakness is an an aneurysm on its back.
- Higher Dimensional Life Form Alien Ihaton: Unknown invaders who have destroyed many worlds but have never once fought an Ultra Warrior. They embody the negative desire of organisms to destroy civilizations. Behaves like a Yandere.