Erebus

Erebus is the Primordial God of Darkness and the older brother of Nyx in Greek mythology and one of the creators of Thanatos, Hypnos, and Oneiroi. Erebus and his sister joined Hades and the Alliance of Hell to eliminate the DxD team, Longinus users, chief-gods of each mythology, and Ajuka Beelzebub.

Appearance
Erebus is a handsome young man appearing in his mid-twenties with black hair. He wears a black cloak and his body gives out dark aura. During the battle, He was shown to be wearing a light-black armor.

Personality
Erebus is shown to be calm and collected in person and deeply care for his sister and later became enraged when she was defeated by Issei. He was also shown to be troublemaker to those who refused to join the Alliance of Hell such as King Enma, who refused to join them and attack the shrines that worships Enma.

History
In the past, Erebus and his sister Nyx created Thanatos, Hypnos, and Oneiroi. At some point, they received a invitation by Hades to join the Alliance of Hell.

Red Dragon Emperor of the Blazing Truth × White Dragon Emperor of the Morning Star: The True Dragon(s) of the Kuoh Academy
Erebus was mentioned in Volume 24 along with his younger sister, who were arriving in the Realm of the Dead for Hades’s meeting.

Erebus made his first appearance in Volume 25, where he became delighted that Mitsuya Kanzaki, who wields Innovate Clear and Telos Karma, has been found and knowledges the Longinus are a threat. He and Nyx trembled at the sight of Issei Hyoudou’s fury towards Hades for sending Grim Reapers to attack his father Gorou Hyoudou.

In True Volume 2, Erebus went into hiding after the defeat of Nyx and made a plan together with Gressil and Sonneillon after they were defeated in the Azazel Cup tournament.

In True Volume 3, Erebus and his group planned to attack King Enma after he refused the Alliance of Hell invitation to join them and encountered Issei in his Diabolos Dragon form at the altar, Erebus revealed to Issei that he considered him a threat after watching the tournament recordings of his matches and it trembled him. Erebus tried to attack Issei with his dark mass of aura, but he repelled it to a different direction and was told to stop his attack at Enma and surrender, but he refused because Enma turned down the invitation and thought of delivering a big blow to Japan. He was asked again to surrender, but Erebus once again refused because Issei defeated his sister Nyx and told him to disappear in the darkness, and as Issei prepares to launch his attack, Erebus formed a dark barrier until Issei used his Penetrate to passed through the barrier and received a punch and dodge his kick, and he was about to be pierce by his Ascalon, Erebus stopped it with his dark aura and managed to damage Issei’s armor. Changing to a different location, Erebus release his godly auras from his hands to launch it and collided with Issei’s dragon deification auras, causing a explosion on the area. In the battle, Erebus begins to question to Issei about him playing a hero despite having so much strength and continues to dodge Issei’s Ascalon attacks while questioning him. When Issei eject Ascalon II, Erebus dodge the flying sword and evaded the other Ascalon and dodge the Dragon Shots, revealing to Issei that he seen his attacks in the tournament match videos. As Issei tried to impale Erebus with his Ascalon tail, Erebus dodged it by twisting his body, but the another Ascalon that was returned to Issei’s left gauntlet pierced into Erebus's abdomen and a received a punch to the face. As Erebus was about to pass out, he enveloped Issei’s armor with his darkness and was struck by Issei’s Dragon Shot before he tells Issei that he was good at tricks, completely lost conscious after the fight.

Powers & Abilities
Immense Strength: As a Primordial God of Greek mythology, Erebus is a very powerful god, however it’s been proven that he was not good at fighting, but was good at tricks.

Immense Darkness: As a Primodial God of Darkness, Erebus is capable of producing dark mass of auras that was able to damage Issei’s Diabolos Dragon’s armor. He can also use his darkness to create a barrier to protect himself from his enemy’s attacks.

Dark Sealing: Erebus can create a dark sealing on his enemies, as seen when he placed a curse on Issei’s armor to prevent him from manifesting Ddraig into battle.

Flight: Erebus has demonstrated the ability to stay afloat in mid-air.