Ok first off I think Scott "leaked" the premise of Nocturnal a while ago...something about a woman who births her nightmares(or am I just making shit up)... So the people who dragged Aggie off and who are killing the gangs(and doing the pissing) are one group of "nightmares" like any group there are leaders and followers(due to strength or smarts) and the kidnappers of the homeless are just picking up chow for the group while the stronger smarter ones do the hunting and gang killing. This group are most likely the first ones and the other ones(mutant dwarfs) are secondary ones that are brothers or in servitude to the first group. I think Rex is actually the "nightmare" woman's only real "human" son or perhaps a "nightmare" Prime that was hid amongst humans to keep him safe or taken away by social services. My guess is that Brian is the "savior" because every time one of the "nocturnals" feels him watching they draw the protection sign and he wakes up(this is just drawing conclusions...) I think the police had a previous encounter and some were bumped off as a warning to stay away and somehow left with the knowledge that they could be killed at any time if they investigated . Woof