Dream, also known as Bliss, is an addictive narcotic sold by assorted drug dealers in the world of Midkemia.
The few users that are mentioned are all whores, and it’s possible that Dream is provided to them by their pimps to keep them addicted and willing to work. The drug’s hallucinogenic properties provide an escape from the crushing reality of their lives (as whores working from brutal criminals in a world with medieval technology), but the need to pay for it embeds them further into these lives. It is a deeply unpleasant situation, and more than one such user of Dream has committed suicide.