Cavalier of the Abyss

Demon Serin is a young, yet powerful, demon of Chaos and the one responsible for Jae-Hyuk's death. During a battle with a rival demon, she accidentally struck down Jae-Hyuk, when Jae-Hyuk was attempting to bring his ill brother to a hospital. Feeling slightly guilty, she asks him "Do you want to live?", to which Jae-Hyuk answers yes. She brings him back from the dead, transforming him an undead, much to his disbelief, and ends up dragging him back to her world, the world of Chaos.

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Depore Magnasetia is a demon stone. Her current master is the Regis Nex, though she originally belonged to the former Regis of Chaos Noche, and later to Demon Astarote.

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Xix, also known as Jyi, is the main protagonist of Cavalier of the Abyss. Like Regis Nex, Xix is an undead, with a deep rooted hatred for the Regis. Xix has single-handedly attempted numerous assassinations on the Regis with little success. He has formed a contract with the demon Skoll, planning to use the demon's strength to help his cause. He wishes to execute his revenge on the Regis for the massacre which took place in the Baanan Clan Village. Xix is a candidate for being the Regis' son as his blood has opened two of the Caladbolg's seals.

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Just is the name Ouroboros takes on after sealing himself inside a deceased body to pose as Regis Nex's son. In further chapters, it was proven that Just is definitely not Nex's son.

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