In the anime, there are four generals: Lucifer, Alciel, Malacoda, and Adramelech, and they all work under the devil. I'm wondering which group of 4 these demons are based on.
I've mostly thought that the 4 princes: Satan, Lucifer, Belial, and Leviathan can be counted out because Satan is included in, but I'm not 100% sure.
There are also the four horsemen of the apocalypse: Pestilence, Death, Famine, and War.
There are also the 4 demons at the Euphrates, but I don't know too much about them.
I'm not sure about any other groups, but I'm sure they must be based on something, the anime was great with tying in the Christian faith into the mix, so I can only assume that they'd include the four generals as some sort of a reference.