This is about the secret society. For the band, see The KLF.
The Justified Ancients of Mummu (The JAMs) are a secret society based on a primeval Babylonian deity, Mummu.
Simon Moon is a member.
The authors associated Mummu with the the idea of primordial chaos in the novel. A Standard Reference Work says Mummu is a craftsman, the personification of technical skill and, as the third of the primordial gods, Mummu symbolizes the mental world, the logos (logic).