Voice Actors: Takayuki Yamaguchi (Japanese), Jeremiah Freedman (English)The main hero and Core Robot pilot, an Ordinary High-School Student who's sent to a parallel world where giant robots fight each other, and ends up surrounded by women.
Voice Actors: Rie Tanaka (Japanese), Michelle Ruff (English, as "Georgette Rose")Mitsuki is the popular girl, and daughter of Dr. Ken Sanada. She lures Kazuki to her house for her father's experiments, but is sent to the parallel world along with him.
Voice Actors: Ai Uchikawa (Japanese), Katie Ashley (English)D is a bioroid, an artificially constructed being. The war between the Earth Defense Force and the Rara Army began when D and at least two mechas were discovered in an alien artifact. She finally returned to her original body in the second-to-last episode.
Voice Actors: Chie Nakamura (Japanese)Former pilot of "Hartzenen" (the white robot) but had the misfortune of being injured and losing that ability. Kazuki saved her life and she fell head over heels in love with him.
Voice Actors: Megumi Toyoguchi (Japanese), Wendee Lee (English)Originally known as "Miss Ra", the Rara Army's spokeswoman and mascot, it's later revealed that she's Mitsuki Sanada's counterpart in the parallel world.
Voice Actors: Ryūsuke Ōbayashi (Japanese), Kirk Thornton (English)
Voice Actors: Mika Doi (Japanese), Diva West (English)
Voice Actors: Kenichi Ogata (Japanese), G. Gordon Baer (English)