Subaru is a second year student at Tanegashima High School.
At a young age, Subaru had a strong interest in robots, but his father had other plans for his future. Despite being skilled with robots, Subaru was made to promised that he would become a fishermen like his father and take over the family fishing business. Subaru promised his father that he would fulfill his wishes, but Subaru would continue to spend time with robots under his father's nose. Taking the guise of Mr. Pleiades to avoid being caught by his father, Subaru enters and wins two Robo-ONE tournaments.
Subaru Hidaka is created by 5pb, and he has no information regarding any inspiration used to create him. He first appears in Robotic;Notes visual novel game and make his first anime debut in episode 1. He is voiced by Yoshimasa Hosoya.
Outside of robot fighting, Subaru is a no nonsense student at Tanegashima High School. He often appears cold and unfriendly. Once he dons his "Mr.Pleiades" persona, his personality completely changes to a point where he is unrecognizable to his normal self. When acting as Mr. Pleiades, Subaru not only has more charisma, but also enjoys flashing his showmanship.
Subaru is shy around women and he blushes when a woman even so much as compliments him.
Subaru generally dons a school uniform or an outfit similar to it. At school, he wears a white buttoned shirt and black pants. Outside of school, he is often seen wearing a black and white shirt with the buttons near his collar left unfastened. When he is playing as Mr.Pleiades, he wears a bright blue shirt that exposes his chest and purple cape. He also wears black pants and white boots with a cutlass at his hip. To his identity, he wears a white mask that covers eyes. This disguise, however, has not been able to fool everyone.
Akiho Senomiya - At first, Subaru had thought that Akiho was very annoying and he only joined the Robotic Research Club because he was being blackmailed. After Akiho had returned a broken piece of his M45, he has gained more respect for her. Since then he has been helping her build the GunBuild. While designing the GunBuild, he advises Akiho and makes sure that her designs and way of thinking are practical even if she disagrees with him.
Furugoori Kona - After being defeated by Kaito in the Robo-1 competition, Subaru sought the help of Frau to make his robot more like Kaito's robot. In the beginning he was ignored and mocked by Frau, but she had opened up after Subaru mentioned that he was helping Katio. Since then the two have become familiar with each other.
Kaito Yashio - Kaito and Subaru had first met sat the Robo-1 competition. Since then, Subaru has grown to respect Kaito for his skills in robot fighting. Subaru has stated before that he is not Kaito's friend.