|Family||Wife: Queen Promethium|
Eldest Daughter: Emeraldas
Youngest Daughter: Maetel
Maternal Granddaughter: Mayu
Dr. Ban is the former husband of La Andromeda Promethiumand the father of Maetel and Emeraldas. He is also one of the scientists responsible for the creation of the Machine Empire while being labeled as a traitor for defecting as well as causing the fall of the empire through Maetel.
Before his conversion into a pendant, Dr. Ban was a middle aged man with shoulder length brown hair, brown eyes, a mustache, a broad nose, and a beard. For clothing he was always seen in a lab coat.
After his body was destroyed, Dr. Ban's consciousness was transferred into a capsule carried by a black ovaloid pendant with a pair of ports on top carried by Maetel. Whenever Dr. Ban speaks, the meter flashes. For a while the capsule even used a cat body until it was burned.
Dr. Ban is a scientist who genuinely wanted to make life worth living. However, he did not always make the ethically right decisions, particularly when agreeing with his wife to convert the La Metalians into robots with Machine Bodies as well as jumping to conclusions based on her suggestions to fuse his mind with hers. This eventually became his undoing as it made Queen Promethium into a soulless machine.
Upon being separated from Promethium, Dr. Ban had regained his emotions but lost his body. Regretting his actions, Dr. Ban resolved to destroy what he had created with help from Maetel. However, this is not to say he is not pushy about what needs to be done in order to be given the right position such as having Maetel play her intended role as realistically as possible. He still cares about Maetel as a daughter and only wants the best for her while being at best estranged from his eldest child, Emeraldas.
Dr. Ban was considered one of the most intelligent people in the Leijiverse, particularly in medicine, robotics, and programming. Through much time and effort, he successfully created the Machine Bodies for a human consciousness to inhabit with assistance from other scientists as well as a more psychologically stable vessel in the form of capsule and pendant. The pendant form he took can store large amounts of data and energy allowing Dr. Ban to heal a badly wounded or injured Maetel and when put into the proper equipment can destroy an entire planet such as the Great Mother Planet. The capsule can also be fitted into other machines including mobile units like a robotic cat.
While it is unknown about Dr. Ban's past before meeting Queen Promethium, he married her and fathered two daughters named Emeraldas and Maetel. With La Metal's artificial sun starting to fade, Queen Promethium had Dr. Ban and other scientists like Hardgear start the project to save the population by giving them Machine Bodies to survive. However the process proved to be too great and unrefined. With Dr. Ban near the end of his life due to the actions of Hardgear, Queen Promethium has him continue the project through her by implanting his consciousness into her mechanized body. Dr. Ban had attempted to convince his wife that what was happening was wrong through the nanomachines placed into her body. Promethium however overpowered his influence and the mechanization turned Promethium into a heartless monster inheriting Dr. Ban's intelligence. Through this she oversaw the mechanization of La Metal's citizens.
When resistance lead by her daughters was put up, Maetel manages to separate Dr. Ban from Promethium. Since then, Dr. Ban was put into a pendant for Maetel to carry and spent the next several years planning contingencies against the Machine Empire. The final result was destruction of the empire; but to keep Promethium from finding out their plans, Dr. Ban enforced Maetel to play her role as guide in spite of the ruined lives that happened as a result. By the time Tetsuro Hoshino became involved, Dr. Ban had Maetel bring him to Great Mother Planet to see if he was suitable to lead the enslaved people away. With the task complete however, Maetel inserts the pendant into a position which causes the planet's destruction. After Maetel and Tetsuro part ways, Dr. Ban continues his journey with Maetel.
According to Takarajimasha's Galaxy Express 999 Perfect Book, Hajime Amamori and Dr. Ban are the same person. This is likely a reference to the rumors surrounding Queen Promethium and the fact that she is Yayoi Yukino to whom Hajime was a close friend with the Millennial Queen. Given the nature of the Leijiverse, it is possible that Dr. Ban might be a descendant or even a clone of Hajime.