Copen's sudden change of heart about adepts would've been more palatable to me if Kohaku was a septimal sheltering minos children from Sumeragi. Him not killing Blade as is was a huge break of character, GV1 & 2 sets in stone that Copen does not tolerate adepts, even if they're trying to help him. The game really needed a reason as to why THIS guy in particular would suddenly take a deep breath and spare the person who tried to kill him on three seperate occasions in the same game, a reason that wasn't just "this random girl's sister". Shit like that hasn't stopped him before.