Our Perverse Pleasures: Just like the Aeldari
Slaneesh is the deity of hedonism and excess, the downfall of the Aeldari race in the Warhammer 40K Universe. The history of the Aeldari is a hauntingly familiar story of the rise and fall of an empire. Giving into complacency, they revel in the seemingly endless pleasure and comforts their wealth provides them. This proves to be their downfall, as the story normally goes. In this particular twist on a familiar story, their downfall is due directly to their pleasures crystallizing an actual god in the immaterial realm of the warp (in the Warhammer universe, beliefs and emotions shape reality, often the gods of people are formed in the warp by their beliefs), a god of pleasure, formed out of their very hedonism.
One would expect this to be a good thing, because of course, isn't a god of pleasure supposed to give pleasure? But that would be misunderstanding pleasure. Pleasure is a good thing, we feel good when we eat, have sex, and other things we consider "good" are pleasurable. But there's also such a thing (and I hope you'll agree with me) as *Perverse* pleasure. Serial killers often find pleasure in their killing, hearing someone scream in agony can sound glorious to mentally debased people (and actually the fact that they derive pleasure in such is the reason we call them mentally debased). The Aeldari were not just finding pleasure in the "normal" things, which if you notice usually involves pleasure not as the only "end" in mind of the act. They were doing things with pleasure as the only goal, pleasure in themselves with any means possible of achieving it. This hedonism forms a god of debased pleasure that ultimately does what a being of its type does best: Pleasure itself, usually at the expense of others.
The Aeldari are doomed to extinction if Slaneesh does not die, and it's not an easy feat to kill a god. But all this backstory was to show some similarities between us and the Aeldari: We are living in a period of great wealth, where even the middle class have more comfort than Kings of a century ago. As a result, we have indulged in more pleasure than was ever possible in the past, and the way this post-modern age is going, where all we are is bound up in the identity of a consumer seeking our own comforts, often at the expense of those worse off in this broken System, we are birthing a monster that will destroy us. Slaneesh is fiction, but hedonism is not. Their fictional story is actually a sort of warning. As fiction often is, the story is mirroring reality, revealing obscure facts and hidden figures in their exaggerations, they often reveal truth in their "lies". We'd better heed their warning.