User blog comment:Tricell/Who/Which are these Demons?/@comment-392782-20120527180218

I think they most likely represent the Seven Vices - the Seven Deadly Sins (wrath, greed, sloth, pride, lust, envy, and gluttony), and the demons are probably servants of Azmodan who hold some sphere of influence over each one. We've seen a few of them in the third game, but not all.