twilight town was all namine's doing. she made sora believe he was someone else. it just clicked...she made sora believe he was BHK. think about it BHK says hes soras guardian, but sora doesn't know him. and BHK only knows OF sora, he goes to namine looking for a direction to travel. i think that BHK was the keyblade master before sora was. and thats how their hearts are connected. through the keyblade. and there must have been some kinda of evil before sora otherwise all the legends of the keyblade could not have been made. a legend has to come from somewhere. and it came from BHK or maybe someone that was keyblde master even before him. and thats how BHK is the other side of sora heart as they say, the keyblade connects their hearts