User blog comment:B214/Volume 22 spoilers/@comment-201.215.165.7-20170208152747/@comment-31137559-20170208155617

Well the 72 Pillars will still exist and the politics will go on. It probably has changed a lot due to Issei's influence because he has turned the whole Underworld and their values upside down. He is engaged to a high-class devil and the little sister of Lucifer, he has become a high-class devil in less than a year, and he has a high-class devil in his peerage. There are a lot of devils that don't look at him favorably like Sairaorg's father for the fact that he has come this far and is only a reincarnated devil. And Issei is already a hero in the Underworld to the common masses so they have to go along with it just to keep the masses on their side. Most will most likely use Issei for political gain. The feudalism won't end. Their culture might have been shaken up a bit but there are still those old devils who will persist.