As for friends, it seems that Hiro and Shuichi have been friends since childhood-early teen years. Even before Bad Luck became an actual band, they idolized Nittle Grasper, though it seems, Ryuichi Sakuma more than anyone, as Shuichi on more than one occaision refers to him as God.
That's all for now. If anyone has anything to add, feel free to e-mail me. Any information would be more than appreciated.