Soporific Musk

The Soporific Musk is one of the most dangerous drugs in existence. It creates a sense of euphoria with the general dullness of the senses for up to a few hours. Extremely addictive many who have tried it constantly seeks to try to gain the same euphoria. They usually resort to other drugs but nothing compares to it. After a while the addict will die without it. Either way, the effect is devastating, even trying it the once alters the creature on a neurological level permanently.
Most who try it seems to crave sensations far beyond any mortal can withstand. It rewires their nervous system in such a way, most can't control the sudden rush. Ever after the creature will try to find stimulation in any number of ways to bring the rush back, all the while they get strange dreams of a being calling them saying that only it or its servants can satisfy their every vice, even for a short while.
What many don't know is the source of the Musk. It is given off in clouds from creatures called Fiends of Slaanesh, demonic entities from another dimension. They extrude it naturally through modified sweat glands, and use it to subdue opponents of themselves & their masters. All fiends, and their masters, are immune to the effects of it, yet mortals aren't, especially Elves. It seems that the Elves are somehow linked to these creatures, how, nobody truly knows. A disturbing fact remains, is that the Elvish races seem to produce trace amounts of the same substance, and if enough are killed and their hormonal glands (especially in the brains of them), a slightly weaker version is able to be synthesised producing the same effects.
Most creatures either ingest it, or inhale it in gaseous form. The latter by burning it if no fiend is present to produce it naturally.