So you want to be a Lord of Darkness
The forces of darkness need middlemen, what you get depends on what the people around you tend to offer for the sometimes ethically shadowy darkness. The forces of darkness get stuff, all kinds of stuff. The problem, for an abstract facet of reality, booze and hookers just dont cut it, even souls don’t get the job done. What they do want is egotism, selfishness and a desire for control and domination, etc (and sometimes hell dimensions of agony torment and suffering, it does not really care which brush the collective efforts of sapient existence want to paint with).
People pray, offer, tithe, bribe, etc the abstract force of Darkness, you Least Lord of Darkness get, well that “stuff”, the Darkness gets to further its aims in the multiverse of the entire place getting just a bit blacker. Sometimes specific actions will be required from you, but mostly the coveting, envy and desire of the people making the initial offerings just needs to get rewarded somehow so they will keep doing it, which if your part of the job.