Wrath, Envy, Sloth, Greed, and Pride.
These are the five Sin Demons who arrived upon the orders of the Demon Emperor.
Previously, it was their comrade - Lust, who was originally stationed in this world. He was supposed to be the one who will put this place under their control but to their surprise, he met his fall here.
Nobody truly expected that this world will put up a fight against them. This backward planet was so small and puny that it's hard to believe that it was possible, yet here they were, called reinforcements to bring the same backward planet under their heel.
When they arrived here under the orders of the Demon Emperor, they didn't expect the command line to be in a mess.
There was no semblance of authority when they got here. Almost all of their soldiers who were trapped here started minding their own business, acting like someone that they were not.