Cults of Slaanesh
Those who venerate the Dark Prince of Chaos in the Old World are wont to form secret coteries, cults, and confraternities, for, perhaps more than for mortal servants of the other major Chaos Gods, their deeds must remain hidden in order to perpetuate. Slaanesh's followers are gregarious by nature, and their rituals require both victims and an audience, though often these are one and the same. No act, no matter how extreme or blasphemous, holds much meaning unless it is witnessed, whether by others who also venerate Slaanesh or by unwilling victims moments before they meet their end. The followers of the Great Powers organise themselves into cults – secret societies of like-minded worshippers who gather in hidden places to practice their vile creed
Commonly, cultists are highly placed members of their communities -- the alderman, the magistrate, the lord, or the trader. Each cult is different, but most feature a highly compartmentalised, pyramid-shaped power structure, with each level ignorant of most of what goes on in the level above. Members hide their true identities from the bulk of the cult, though it can be guaranteed that someone will know their name and thereby hold power over them. Many cults are sprawling networks that employ their own staff s and agents, own properties, and conduct themselves more like a business or criminal enterprise than a body of worshippers. Yet, whatever form the cult takes and whatever masks it wears to disguise its true face, it is above all else a sect of men and women dedicated to the worship of a forbidden god
Many cults have existed for decades, centuries, or, occasionally, millennia. Over generations they have spread their influence far and wide, working towards some end only the most senior of masters is aware of. It is likely that the lowest ranked cultists, whatever they do by day, are mere foot soldiers in the cult's great undertaking and they are only allowed to glimpse a small portion of the greater plan. The exact nature of this grand undertaking varies enormously, though most have several points in common; it invariably promises a time when the cult will be able to throw off its disguise and rise up against its oppressors, tearing down or taking control of the prevailing social order.