I actually read the thing and keep reading it so I' think I rememver a bit. The Noahs are apparently this clan of ancient monsters/spirits/original humans that have been aroudn since the great flood, and continually reincarnate themselves into ordinary people, subsequentially taking over their souls minds and bodies, as the case of Allen Walkers continuous fight against the fourteenth. They are lead by this demonic fat guy called the millenium earl, who for all I know has the orignal noah.
Welcome one and All to the Jesters Carnival, where the prizes are greater than your wildest dreams, but the nightmares here shall silence you before you can even scream.