Charlie Morningstar is daughter of Lucifer and is the princess of hell. Hell is dealing with a massive overpopulation in one of the 7 rings, the ring of pride. This is because earths sinners get sent to the ring of pride and cannot travel to the other 6 rings, Greed, Wrath, Lust, Sloth, and Gluttony. Only hell born demons can travel between the rings. Every year in the ring of pride, there is a "cleansing" where exorcist angels kill a mass amount of demons to reduce the population.