The Black★Rock Shooter Universe is an original concept created by Huke himself.
Ryo is inspired to make a song after he looked at Huke's graphics at Pixiv. That time, Huke joined Supercell as their creative member. After Ryo told Huke that he wanted to composed a song about B★RS, Huke is interested and he makes his final adjustment to B★RS. He added uneven ponytails to B★RS.
All of Black★Rock Shooter's Characters are taken from an Arcana Mayor card. Their character designs symbolize some Arcana Mayor's card. B★RS Character represents "Star". B★GS represents Devil, Death Master represents "Death", Chariot represents "The Chariot", and STRength represents "Strength".
Huke too is making lots more of character to the serial of B★RS.
It's known that some of these characters including the most awaited character, White★Rock Shooter, has appeared on the B★RS GAME for PSP. In the game, W★RS and B★RS are voiced by Sakamoto Maaya. W★RS has the role of the final boss in the game.