Cavalier of the Abyss Wiki
Demon Nexus Nex

The Human
The Regis
The Sun
The Night Which Speaks of The End


Human (Formerly)


Male.png Male


Immortal Regis: 16

Flashback Arc: 18

Currently: Somewhere between 35-40


182 cm (6'0")

Hair Color

Dark Brown

Eye Color

Red (Undead)

Professional Status




Personal Status



Miya Noah (Daughter)
Siana Nexus (Daughter)
Ninoorut Noah (Son)
Chae Jae-Hoon (Brother)
Demon Serin (Lover)
Iffrita Noah (Ex-Wife, deceased)


Undead Abilities
Negative Magic



Image Gallery

Demon Nexus Nex (born Chae Jae-Hyuk) is a main protagonist of the Cavalier of the Abyss manwha. He has deep affection towards the Demon Clan's Demon Serin, and has had two children, Ninoorut Noah and Siana Nexus, with her. However, he has since imprisoned her and labeled her a traitor for currently unknown reasons. He also has a daughter with Iffrita Noah, Miya. He is the Regis of Chaos though most of his territories have been take over during the Second Magnanix.


Regis Nex has brown hair and wears royal clothes with a cape. His clothes usually have fur. He can adjust his clothes with magic. When in battle he has his sword Depore and usually takes off his cape.

Many characters in the series, particularly girls have stated that Regis Nex is very good looking often being charmed with his natural good looks.

There is a massive scar that has been placed on his back when Demon Serin stabbed him in the back.


When Regis Nex was young he would help everyone in need. He was kind and very protective of his comrades, especially Serin. However, as time moved on Nex changed completely and became cold and merciless towards both allies and enemies alike. It was a result of Serin betraying him and running away from him without explaining anything. Also, having lost his brother to Caladbolg, causing him to have a experienced great pain.

His cruelty is only a facade as during a conversation with Caladbolg and after seeing the demon slaughter his men and innocent civilians absolutely horrified him, showing that he does care for his people, and after the talk, he resolved to kill the latter.

One aspect is that he vehemently denies any relation with the Night Clan. As the Night Clan corrupts and mutates anything in Chaos into horrific monsters Nex feels rejection towards anything regarding the Night. It is also stated by Depore that despite his cover as a cold and ruthless ruler he is racked with so much guilt over his actions over contaminated areas such as Baanan that he can barely sleep and has chronic nightmares all the time.

When it cames to his children, Nex shows his caring side, always treating his daughter Miya as a treasure, and valuing her above all else. However, Nex would treat his son, Ninoorut, with complete indifference, due to the assumption that Ninoorut was not his son.

Later it was revealed that he had intended to give Ninuroot the throne all along regardless of blood, but he pushed him away so that he doesn't become a fear ruler This shows he has no prejudice for the Ninurta , but wanted him to grow up as a kinder and better ruler than him showing that despite all the tragedies he suffered throughout his life, at heart he retains the kindness he displayed in his youth.

Nex's cold demeaner was formed from the heart-breaking betrayal that he has suffered in the past and due to the people him that are constantly scheming for power he's very cynical of people's intentions but at heart he's a good person. His close friend Owen has stated that he is a very kind person who shows needless kindness towards people despite suffering much sorrow throughout his life.


Young Nex in the human world

Long before he became the Regis, Demon Nexus Nex was named Chae Jae-Hyuk and lived with his young brother, Jae-Hoon, in a small one room apartment in the human world. The young Jae-Hyuk spent most of his time traveling between school and multiple part-time jobs, so that he could take care of his sick brother.[1]

During an unfortunate night, while trying to get his sickly brother to the hospital, he is accidentally injured by Demon Serin during a battle, and dies. She brings him back to life as an Undead but because his mere proximity to his ailing brother was slowly killing the young Jae-Hoon he accepts having to go to Chaos with Serin so that he can learn to control his powers and later return to his brothers side. Sadly, his brother is possessed by Caladbolg which results in him cutting all ties with Serin who brought the child over for medical care. After dueling Caladbolg and cutting alliances with Serin and his former school friends he chooses to travel alone with Depore as his sole companion.


At the beginning of the story, Regis Nex is shown traveling with his warriors to a neighboring village in order to destroy a traitor.[2] One of his warriors pleads for Nex not to slaughter the entire village which Nex quickly attacks the man for defying his word. Soon enough, the traitor and anybody deemed a follower was murdered. Nex, then travels to meet with Princess Yuan, the woman engaged to Prince Ninoorut.

Nex confronts Xix

When the Princess arrives, Nex can easily detect the hostile energy radiating from Xix, but pretends to not notice it until he is close enough to strike both Xix and Yuan down easily. Xix is shocked by how easily Nex was willing to let the Princess die alongside him and takes the blow meant for both. Xix and Nex quickly duel with the Regis, along with Depore, proving to be the stronger combatant. During the middle of the duel, Nex is surprised to learn that Xix is another undead. But despite his shock he easily rips Xix's heart out and gloats over how an undead can still suffer some forms of pain.[3] He then orders for Xix to be dragged back to the castle as they return for the engagement ceremony.

Nex takes blood from Serin

Upon return, the Regis commands Yuan to meet the Prince. When Ninoorut attempts to show his father respect, the Regis snubs him publicly much to the Prince's humiliation. While the engagement commences, Nex steps out to go shower for the event. While his maids bathe him, Iffrita and Nex discuss about how silly her constant worrying over his well-being since he always returns home fine. A maid discovers that an injury Xix dealt him earlier still hasn't healed and Nex grows irritated and begins stalking off but is stopped by Iffrita, who attempts gaining her husband's attention.[4] He coldly dismisses her and heads off to the Great Betrayer's imprisonment chamber; Demon necromancer Serin.

When Nex sees the catatonic woman he is quick to gloat over how her betrayal led to her current situation. His hostility increases until he savagely bites into her to drain her healing blood.[5] After his wound his healed, he is quick to tell the unresponsive woman that as long as she is alive he will keep her in this state.

Xix interupts the ceremony

After his injury is healed, he returns to the ceremony and watches on in apparent absolute boredom. In the middle of the ceremony, Navarus interrupts the ceremony much to the shock of everyone, but Nex who finds the situation amusing.[6] Navarus claims to have found Nex's true heir and that Prince Ninoorut is a fake, which Iffrita is quick to dismiss as lies, while Nex asks for proof. Before Navarus can introduce the apparent heir, Xix reawakens possessed by the demon he had formed a contract with Skoll.

Skoll possessed Xix quickly strikes down several of the Imperial guard when the Prince steps in to fight, Nex watches with slight interest. While Xix and Ninoorut duel, Depore awakens to warn Nex that another evil has awaken. When Ninoorut is overpowered by Xix, Navarus's claimed true heir, Just, makes his appearance. Just easily overpowers the possessed undead being another one of Osky's evils himself; Ouroboros. Just is about to land the killing blow on Xix when Nex finally steps in to stop him.[7] Nex is suspicious of Just and questions him on being Serin and his child. He is especially interested in whether or not Just knows about the demon stone, Semek, that Serin had wielded. Just claims to be unaware of where the stone is, and Nex does not look appeased by this answer, but nonetheless accepts it as true. While they are discussing Just's legitimacy, a returned normal Xix makes his escape and Nex orders him to be killed upon found.[8]

Nex visits Osky

Nex recognizes Skoll as one of Osky's creations and quickly travels to meet with the creator of evil. His main objective is to find out more information on the demons and if Osky is aware on whether or not Just is his true heir. When he meets with Osky, he quickly loses his temper when Osky taunts Nex about asking his first wife if Just is their son or not.[9] While he doesn't find any information on whether or not Just is truly his heir, he does find some information on Xix's hatred towards him.

After his meeting with Osky, he is informed on Miya's kidnapping by Night Clan members.[10] He travels to Thanatos where she was taken. When he finally arrives, he interrupts a battle between Owen and Seon Yu, his old classmates under Mistress Infinity's.[11] Seon Yu heatedly proclaims Nex as the slaughterer of his people and fiance, to which Nex reveals it was Seon Yu who was the true murderer all along in a state of madness.

After Caladbolg returns to Chaos and starts the second Magnanix, Nex is currently recovering from his wounds in Osky's mansion and has officially entered an alliance with Osky in order to stop the Night's invasion and kill Caladbolg once and for all. After learning the events of the past Nex and Xix fought their final match to settle their differences which ended up with his victory over Xix. In the end after learning about Just and Caladbolg's intentions to destroy Serpant and marry Siana, Nex officially made Xix a knight of Chaos and teamed up with him to stop the two, one and for all.

Powers & Abilities

As the Regis, Nex is the strongest warrior in Chaos with his strength be well known in both Chaos and in the Night with Osky himself referencing Nex as "Chaos's best". Multiple characters in the series have mentioned his tremendous strength. Just, one of Osky's most powerful evils frequently wondered if he was really a human due to his monstrous, obscene, strength. Siana, a powerful necromancer and member of the Night remarked that if she did not hurry up with her mission, forget about completing it, she might not even survive if Regis Nex starts attacking. During the first Magnanix it was Nex that broke Caladbolg to pieces and would have successfully killed him if Serin had not intervened.

His strength is so tremendous that Osky, a legendary sage and being equal to that of Caladbolg mentions that Regis Nex possesses the fighting ability that of a God frequently showing extreme fear whenever Regis Nex is around. When the second war began Caladbolg personally prevented his brother from launching an assault on him by stabbing his entire body with spears when he returned to Chaos confessing that even he could not hold back against his brother if he attacked despite his critical condition hinting just how formidable his abilities are.

As an Undead, he has increased strength, speed, endurance, accelerated healing, can siphon the life-force of people around him to accelerate his healing, negative magic (can be used to create armor, dark claw, etc.).

  • Dark Claw "True Form": Nex uses the Dark Claw to clad himself in a suit of black armor.[12]
  • Negative Magic: Nex possess a unique form of magic that is considered "minus negative magic" a powerful form of magic that is said to be extinct in Chaos. As noted by Brass this makes Nex a very special undead with great potential. Nex is noted to possess unimaginable amount of magic as a loss of control of magic was nearly able to kill Osky, Yuan, and Xix by accident. In fact he would have succeeded if Osky had not calmed Nex down with Xix and Yuan being utterly powerless to stop him. Osky has noted that Nex possesses the greatest amount of Negative Magic which made showing him the truth about the past complete suicide as a loss of control could end up killing all of them.
  • Barrier Magic

Master Swordsman: Nex is an tremendously skilled with the sword as he was able to easily defeat Ninurta in a duel of swords despite the fact that he was going easy on him.


A striking technique originally used only by members of the Serpent Clan, it can be used by those who have a body structure similar to serpent, however for those people, overusing the technique comes at a great cost to the user's life span. There are 9 levels in Tae-Gyuk, Regis Nex achieved up to the 8th level, but did not try to reach the final level because of the cost to the user's life span.

During Xix and Nex's duel after learning the truth of the past its revealed that Nex's Tae-Gyuk is far superior to Xix's own, a fact that Xix himself noticed as his abilities were easily nullified by Nex's own attacks.


A demon stone who is able to transform into different types of weapons. While fighting Caladbolg, Nex draws upon Depore's power in an effort to behead Caladbolg. At the same time, Depore is not indestructible, as seen when Nex's sword cracked after Caladbolg stopped Nex's "Depore Square" attack [13], which was partly due to the fact that Depore's powers were drastically weakened after the Magnanix.

  • "Dual Blades" - Depore's form is changed from one large blade to two smaller ones.[14]
  • "Down Time Square" - freezes the opponent temporarily. Nex is first seen using this technique on Caladbolg upon their encounter in the Banaan Clan Village.[15]
  • "Depore Square" - Depore's density is multiplied, thereby giving much more force and deadliness behind Depore's swing.[16] Also first demonstrated (albeit unsuccessfully) on Caladbolg in the slaughter of the Baanan Clan Village. Misuse of the technique could result in Depore sustaining damage.


  • "You're still the same. Your body's being tortured, your mind being eaten by nightmares... It's a punishment worse than death... The traitor of Chaos. The one who betrayed me. Ironic, don't you think? If you aren't alive, I also can't go on living. As long as I need your blood. You are mine. A piece of bone, a drop of blood, all of it. I'll never let it go. Serin." - Regis Nex to Serin, in Chapter 5.
  • "Claiming to be my son, and even running away, I can tolerate them. However! Rebelling against me... I will not forgive. Go ahead and vanish along with those you care about." - Regis Nex to Xix, in Chapter 45.
  • "If there's a life I can save, if that someone desires my help, I will not stand idle while that life vanishes right in front of me. That's my sense of justice." - Jae-Hyuk, Ch. 34

Chapter Appearances


  • His original name was Chae Jae-Hyuk before Serin named him Demon Nexus Nex.
  • His sword is Depore Magnasetia.
  • It hinted that Serin and Nex were the previous couple that saw the dragon up close 10 years ago during the Serpent's Dragon Festival that Yuan and Xix participated in.


  1. Cavalier of the Abyss chapter 21, page 8
  2. Cavalier of the Abyss chapter 1, page 1
  3. Cavalier of the Abyss chapter 3, page 12
  4. Cavalier of the Abyss chapter 5, page 7
  5. Cavalier of the Abyss chapter 5, page 15
  6. Cavalier of the Abyss chapter 6, page 21
  7. Cavalier of the Abyss chapter 10, page 18
  8. Cavalier of the Abyss chapter 10, page 25
  9. Cavalier of the Abyss chapter 12, page 24
  10. Cavalier of the Abyss chapter 14, page 21
  11. Cavalier of the Abyss chapter 18, page 26
  12. Cavalier of the Abyss chapter 33, page 22
  13. Cavalier of the Abyss chapter 67, page 18
  14. Cavalier of the Abyss chapter 24, page 5
  15. Cavalier of the Abyss chapter 67, page 14
  16. Cavalier of the Abyss chapter 67, page 15