Neo-Great Satans

The Neo-Great Satans(新大魔王; Shin ' dai Maō), also known as the Royal Guard(王宮衛兵; Ōkyū eihei) is the new title given to seven devils considered the new rulers of the Underworld and Leaders of the devils after the events of the Great Apocalypse in Highschool DxD: Яe-birth.

Besides the original Lucifer, Beelzebub, Asmodeus and Leviathan titles, three new ones were invented in order to bestow new profiles.

Summary
The Seven Great Satans, also known as the Royal Guard, are seven devils who received the title as the new leaders of the Underworld and the devils by Grandmaster Millicas, the strongest devil and de facto Ruler of the Underworld after Zekram Bael's death. Those devils are considered the pinnacle of the Underworld's Strength and as strong as their own predecessors, and as such, have permission to descend better judgement on Underworld affairs, although unable to take action in affairs of bigger scale, such as Peace Conferences, without Grandmaster Millicas' permission.

After the events of the Great Apocalypse and the death of Ajuka Beelzebub, Sairaorg Asmodeus, Diehauser Leviathan and Vali Lucifer, Grandmaster Millicas bestowed the title of neo-Satans to seven devils who have been known as the strongest of their generation. Although the Grandmaster wanted to share the general authority to all of them, they instead chose to fight each other and decide their positions by eliminations, Cohen Alastor being the ultimate champion of the massacre and therefore crowned as the Lucifer. Three new titles were created to fairly distribut power to other three individuals: Belphegor, Satan and Mammon.

Being successors of the previous Four Demon Lords, their power far exceeds that of an Satan-class devil and by many the power of the original Satans, almost a match to their predecessors. Their bodies are also living seals to the balance of the physical Underworld and if by any change all of them are killed, it might also cause the downfall of the devil world. They're also the only authority to wield the Royal Chaos Havoc weapons and the last response to any affairs in Devil Society, although they rather not get involve in other's affairs by theirs.

Trivia

 * Of all the members of the Neo-Satans, Cohen is the only one not born into the original 72-pillars.
 * Also, of all members, Barzini is the only one who's a single child.
 * Zoroaster is actually the fourth generation of Great Satan, considering that he actually defeated the previous Leviathan satan.
 * Just like the previous incarnation, no member is allowed to have a harem.
 * So far, only Mary and Calico are the satans married to each other, and both Lunamaria and Zoroaster are in a relationship.