Abbadon

He is one of the antagonist that participated the assassination of the Roswell Household.

Personality
Abaddon is a typical Enhancer: determined, head-strong, and simple--sometimes disrespectful. Like all members of the Demonic army, Abaddon never hesitates to kill and is remorseless in doing so. He particularly enjoyed to fight against skilled opponents, but typically rushes into battle without a plan. Although he prefers to fight alone, Abbadon becomes stronger when fighting with a partner because he fights better when there is someone else to protect.

Assassination of the Roswell family
Along with the help of Abigor weapon Vajra that he have stolen he manage to destroy the protected gate of the Roswell's. When he succeeded at slaughtering everyone in the mansion he was attack by the F.U.C. leaded by the Aavely family member Rei S. Lavely.

Abaddon retreated after many of his men got lost but he himself was inflicted by one of Rei's bullets of plagues that gave him a terrible diseases that crystallized his left arm and eye.

Great War
After waiting for 10 years he was cured by Hecate's magic he manage to harden his own body letting him to attack anyone without worrying but it shut down his sense of speed and his languages.

He participated the war in northern Europe with the help of Orobas and Stolas. He was ultimately killed by one of the members of Ona and a former Roswell name as Revis Roswell.