Jin is Natsuki's older brother and is also one of her co-workers at the restaurant that their father owns. He constantly makes his sister angry when at work which gets him thrown out of the restaurant, usually breaking a window on the way out. Everything he breaks due to this act is taken out of his paycheck.
Shu is "plucky," daring and doesn't think before he acts. He usually will run right into a problem on his own, without thinking or talking to anyone about it. He has a special relationship with Kluke that he isn't willing to admit out loud. Shu has the blue dragon shadow, whom Jiro and Zola were looking for at the beginning, because of its unspeakable power. Near the beginning, he doesn't seem very bright but as the story moves on, many can see how strong his willpower is. Shu is practically obsessed with knight masters and that's what led him to find Jiro and Zola, whom he thought was a true knight master. Along his journey with Kluke, Jiro and Zola by his side, he has met the perverted, yet all-for-justice Marumaro (with the Saber Tooth Tiger shadow) and Bouquet (with the unable-to-fight Hippopotamos shadow), his "bride-to-be."
Tatsuya is the main protagonist in the story. He is very knowledgeable about the moon and the Kingdom of Sphere because he has been interested in it since he was very young. He has this odd unconscious habit of pinching girls on the nose as a sign of affection. Tatsuya constantly finds enjoyment in teasing Natsuki about random things.
He is Takeshi's assistant, who is usually addressed as "Faithful Assistant" and replies with "Yes, Master?". He is quite often used to retreat from different situations when in a pinch as he's fast at running and gives a piggyback to Takeshi.
President of the United Nations of Earth.
Karen is the Military Ambassador of the Kingdom of Sphere. She seems to have a fairly strict attitude on things which fits her profession well.
He is the son of one of the noble families of the Kingdom of Sphere. He was initially chosen to be Feena's fiancé, but she instead falls in love with Tatsuya. Unlike the princess, Jürgen hates the people of the Earth, thinking them to be inferior, and wants to re-start the war between the two worlds. He attempts a coup d'etat of the Royal Family, and in total desperation, tries to kill Feena. In the end, Tatsuya prevents the attempted assassination and Jürgen is arrested for treason.