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Martial Arts

Cheon Yeo Woon is the Main Character of Nano Machine (Nano Mashin, 나노 마신, 喇勞 魔神) and the sequel, Descent of the Demon God (Descent of the Mashin, 마신 강림)


A young man with a pale handsome face, long black hair and matching black eyes. After going through multiple Body Reconstruction, he attained clear white skin with tight, well-built muscles. He usually wears dark black luxurious robes with a red cape.

He had long hair that reached down to his back and a pale white face. He didn’t seem like he had any internal energy, but he had sword and blade on his back and waist, proving that he was a martial artist.

NM Chapter 150[2]

Although his eyes were sharp and he had a mysterious aura around him, there was no sign that said that he had been training in martial arts. He just looked like a noble family’s young lord.

NM Chapter 402[3]


Cheon Yeo-Woon was a boy, but he was not a fool. He had overcome many hardships and assassination attempts that made him stronger and smarter. He knew the importance of a weapon if he had one, and also knew he had to keep it a secret if he were to keep himself alive. He was notorious for being kind to his subordinates but extremely ruthless to his enemies.

"I have to keep it secret that I have Nano Machine in me."


He was a member of the Cheon Family and was the son of a female servant who worked at the Lord’s chamber and was not from the Six Clans. Although considered as an illegitimate son of the Lord due to a servant mother, he was still part of the Cheon family and he had the right to the throne but had an extremely low chance without support. He doesn't learn any martial arts in his early 15 years due to his oath with the Lord's wives from Six Clans. After entering the Demonic Academy, only then did he learn Martial Arts and have an unimaginable growth rate due to Nano Machine'a support.


Nano Machine[]

He was a member of the Cheon Family, the highest-ranked family in the Demonic Cult. Cheon Yeo Woon was born to Cheon Yu-Jong, the 23rd Lord of the Demonic Cult, and his seventh wife, Lady Hwa. He along with his mother, Lady Hwa were ostracized by many followers, because Lady Hwa was originally a mere servant who did not belong to any of the Six Clans that influenced the Demonic Cult. The antagonism for further exacerbated because the Lord favored her mother over his six other wives who hailed from the Six Clans. Over the years there had been many attempts over Cheon Yeo Woon and his mother's life.

Out of spite, the six wives led by Lady Mu approached Lady Hwa during the Lord's absence and made her promise that Cheon Yeo Woon was forbidden from learning martial arts until he entered the Demonic Academy. Mere months later, her mother fell victim to Lady Mu's wicked designs and died of micro-poison. Cheon Yeo-woon was entrusted to Guard Jang, that serve as his sole paternal figure. Since then, the child bore resentment towards his biological father, blaming him for abandoning him and his mother.

Even after Cheon Yeo Woon's chances of becoming the new Lord had decreased compared to his other half-siblings, he was still a victim of many assassination attempts, especialy when the Demonic Academy was opening after ten years. That one night, when he is badly injured by assassins, He was unexpectedly saved by a stranger who kills the assassins. The stranger then injects Nano Machine within his body before vanishing. Guard Jang locates his body being fully recovered and asleep and brings him to his residence.

The next morning, he was shocked to discover about Nano's existence and the machine has refined his body removing all blockage in his blood points to help him learn martial arts and cultivate better.

A few days later, he enters the Demonic Academy and is subjected to discrimination making his number 7 badge missing. On the first test, the elder of the Sound Clan, Hang Soyu, increases the intensity of her sound martial art in an attempt to injure him since he was unharmed to the attack thanks to Nano's protection. To avoid suspicion, he orders Nano to injure him internally and is sent to the infirmary to be attended by the academy doctor Baek Jongmeng. Due to his feat in the first test, the Right Guardian, Seob Meng, incorrectly believes that he passed the first test through sheer willpower and is impressed. Seob Meng then visits him at the infirmary and offers to take him as a disciple. Over the next few days, the Right Guardian gave him a manual of Breathing of Thousand Martials and then forcefully transfers internal energy into his body and imparts him his personal martial art, the Butterfly Blade Dance.

Over the next few months, he overcomes many challenges and improved drastically in his cultivation and martial arts with the help of Nano. He visits the Precious Library floors and memorizes all the martial arts manuals that was kept there. He also discovers sapphire monoliths on each floor that has sword slashes and engravings on it that contains one formation of Cheon Ma's legendary Sword Force of the Heavenly Demon and Sword Demon's Destructive Sword Technique. He mastered many martial arts and decodes the two legendary martial arts from the monoliths, thanks to Nano's training program, specifically the Augmented Reality. He also defeated Cheon Mukeum in their fight after he came out from the infirmary, the he proceeded to defeat Cheon Wonryou on the second test cutting the latter's arm using the Butterfly Blade Dance.

When preparing for the third test, he noticed that Baek Gi was poisoned and tracked the perpetrator as Cheon Jongsum. On this occassion, he was provoked by Cheon Jongsum who slandered his dead mother. This angered him to the point that he brutally lynches his half brother and was left with his dantian being destroyed and bones being shattered making Cheon Jongsum crippled for life. This action leads to Cheon Yeo Woon stripped of his badge as a group leader and put in the Detention Center as a punishment. In a fortuitous encounter, he discovers an ancient chamber with a large pillar at the centre with the engraving of the Sword Force of the Heavenly Demon and a ceiling studded with dazzling crystal orbs. he discovers that the crystals contain the long-lost breathing technique and energy flow of the Sword Force of the Heavenly Demon created by Ancestor Cheon Ma himself as well as an engraving of a map at the back of it.

Two months after entering the Demonic Academy, he completed the fourth test in a record time as fastest in the history. After memorizing the martial arts on the fourth floor of the Precious Library, he wrote martial arts manuals and give it to his cadets before finally goes into closed room training that lasted for three years. At the end of the period, he enters the Grandmaster Prowess of cultivation, a feat no one had achieved while studying at the Academy. After emerging from seclusion, he cut off the arm of Cheon Kungwun due to the latter attacking his retainers, namely Hu Bong and Mun Ku. After the incident, he undertakes the fifth test which is to pass through the Sealed Demon Cave. After exploring the labyrinth for a while, he noticed that the layout is somewhat familiar and asked Nano to display the map formed in the back of the dazzling crystal orbs. After following the map, he discovered the Sealed Cave and destroys the entrance. After opening a hole in the cave by utilizing the fourth formation of the Sword Force of the Heavenly Demon, he was confronted by a rampaging black Imoogi, but after exchanging a few blows with it along with Nano's augmented vision, he realizes that the creature is a mere illusion created by twenty four metal fragments. After confronting it with the basics of the Sword Force of the Heavenly Demon, the Imoogi vanished and the fragments assemble to reveal the original Heavenly Demon Sword that was once wielded by Cheon Ma. After touching the sword, he was put into a dark space where he saw the confrontation of Cheon Ma and the Imoogi. During this time, he unwittingly gulps some of the Imoogi's black blood, which detoxifies his body and improves his power, the demonic energy stored at the sword became one with his internal energy allowing him to manifest black qi at will. He also gains one of the severed horns of the Imoogi, which he has it forged into the White Dragon Blade.

Afterwards, he entered the fifth floor of the Precious Library, where he memorizes all the best martial arts within the Demonic Cult that was kept over there and learned the last formation of the Sword Force of the Heavenly Demon, completing the martial art. He decides to undertake the sixth and the final test of the Demonic Academy which last happened 70 years ago. The test was to fight one of the twelve Council Elders. He initially chose to duel the First Council Elder, Mu Jinwon but due to circumstances it was changed. He then confronted the leader of the Poison Clan, Baek Oh in a death match. After enduring Baek Oh's poison, he beheads the wicked old man, becoming the first to complete all six tests after 70 years since his grandfather, Cheon Inji. After the test, he becomes eligible to be a Council Elder of the Demonic Cult.

Shortly after the test, the Left Guardian, Lee Hwamyung has a private discussion with him where the Guardian reveals that he is aware of Cheon Yeo Woon recovering the long-lost Sword Force of the Heavenly Demon, which makes the youth the true successor of the Demonic Cult. The Left Guardian then pledges allegiance and to support him in becoming the Vice-Lord. The Left Guardian narrates to Cheon Yeo-woon about the legend of the Sword Demon and his fight against the infamous Blade God. He was taken by the Left Guardian to the secret basement where the secret manuals of the Sword Demon's martial arts as well as traces of the Blade God's skills have been preserved. After scanning the manuals, he learned the True Demon Sword and the Twenty Four Demon Sword Art. With the help of Nano, Cheon Yeo-woon decodes and learns six formations of the Extreme Art Of The Blade God by scanning the traces left on the preserved arm and skins and practicing the martial art.

Few days later, the last remaining rival,Cheon Muyeon attempts to frame him by sending his subordinates from the Six Clans to go against him. However Cheon Yeo-woon turns the tables by using different martial arts to kill them, and frames Cheon Muyon, who is taken to the Detention Center. Later, he leave the Demonic Academy to seek the support of three Council Elder who would vouch him for the position of the Vice-Lord. He approaches the 11th Council Elder, Huan Yi, head of the Flying Phantom Clan. Huan Yi then test him where he see through the disguise of the elder. After that, they moved on to a confrontation by using blade techniques where he overwhelm the elder leading to the latter pledging allegiance and agree to support him as a Vice-Lord.

Afterwards, he visited his old residence, but is suspicious when he finds that Guard Jang is missing. Upon further investigation, he realizes that this is a trap in order to cripple his movements and seeks to crush him. On the designated night, he arrives at the Poison Clan's manor, seemingly unarmed. Lady Mu attempts to blackmail him, but he retorts by giving her a box containing her son's eye that Cheon Yeo-woon had personally gouged. Lee Hwamyung barged into the manor with the head of Sun Ginung then comes Huan Yi alomg with his troops to encircle the area. His members then bring Cheon Muyeon and Mu Jinyun to the manor where Cheon Yeo-woon slashed the two young man in front of a devastated Lady Mu, as retribution for killing his own mother. Lady Mu shows no remorse and insults Lady Hwa, but Cheon Yeo-woon retaliates by blinding her and slashing off her jaw. Upon hearing how Lady Mu had tortured Guard Jang, Cheon Yeo-woon dumps corpses of the Poison Clan and has members of the Dark Clan killed by Lee Hwamyung and Huan Yi. He pours poison over the corpses and kills Lady Mu in cold blood, making the entire matter look like infighting between the Dark and Poison Clan.

The next day, he approached the 10th Council Elder, Yeon Mu Hwa and wins her support by defeating her and offering her the martial arts of the Sword Demon and help her clan receive the acknowledgement of being the Sword Demon's true successors. Finally, he visits the 9th Council Elder, Sama Yi who promptly agrees to endorse Cheon Yeo woon and offers his daughter to be married to Yeo Woon, where the latter declined. When the Lord and other elders return from their secret expedition, he along with the three elders appeal to the Lord for officially make him a Council Elder after passing the sixth test of the Demonic Academy and then the position of the Vice-Lord. As a warning, Cheon Yeo-woon subtly goads the most powerful elder, Mu Jinwon, and kills him in front of the council. The lord agrees to appoint Cheon Yeo-woon as the Vice-Lord.

That evening, a banquet is hosted to establish the new alliance between the Demonic Cult and the Martial Artist's Alliance. The banquet is interrupted by a stealth attack by the Blade God Six Martial Clan. Fortunately, the cult wards of the attack. However, Cheon Yujong becomes increasingly paranoid of Cheon Yeo-woon's increasing power and begins to suppress him. To gain further strength, Cheon Yeo-woon approaches the 8th Elder Mun Yun and gains his support. He also cripples Cheon Mukeum, the last candidate for the Vice-Lord. Days later, the Great Guardian Marakyum discovers that Cheon Yeo-woon has inherited the martial arts and the sword of Cheon Ma. The Great Guardian decides to support Cheon Yeo-woon and explains that by inheriting the sword, Cheo Yeo-woon has inherited the name of Cheon Ma.

Meanwhile, Cheon Yujong attempts to suppress Cheon Yeo-woon by scattering his subordinates. He also attempts to frame Cheon Yeo-woon for murdering the 2nd Elder (although this was because the 2nd Elder had used the Blood Reversion Art, which is forbidden by the Demonic Cult). Cheon Yeo-woon tricks Cheon Yujong by suddenly appearing at the Great Hall. He rallies the Great Guardian and other elders against Cheon Yujong and reveals the Heavenly Demon Sword. Cheon Yeo-woon defeats Cheon Yujong who faints. It is revealed that the Lord was being controlled through subtle illusions by the Blade God Six Martial Clan. After the culprits are captured, Cheon Yeo-woon is declared the new Lord of the Heavenly Demonic Cult as well as the second Cheon Ma. Cheon Yeo-woon disbands the six clans and brings the rebellious elders under his control through parasites.

With all his enemies subjugated within the Heavenly Demonic Cult, Cheon Yeo-woon sets his sights onto the other powers of the martial arts world. He and his followers embark on a long campaign to secure the spiritual cores of the five spirit beasts and prevent the Blade God Six Martial Clan from achieving immortality. In this process, the Cult gains more strength and influence. The cult vanquishes the Forces Of Justice, the Forces Of Evil, brings the North Frozen Palace under its rule and gains the support of the Imperial Palace. Cheon Yeo-woon assimilates the spirit cores and defeats Blade God in a time machine. However, the machine is damaged, and Cheon Yeo-woon crash lands into the future.

Descent of the Demon God[]

The leader of the thousand demons, the Demon God Cheon Yeo-Woon. Due to an unfortunate accident, he had been sent to the distant future and was now stuck in an unknown world. This is a world where he had went missing, leaving his Cult in chaos and allowing his enemies to regain strength. The Gates have opened, the future is now in chaos and he must fight to return back into the past.

Notable Dismemberments[]

Most of the enemies that he encountered was fated to have one or both of their arms cut clean off. So far, all of his victims whose arms have been cut off directly by Cheon Yeo-Woon himself already surpassed atleast 20 in the novel.

  • All Cheon siblings except Cheon Jongsum
  • Former Lord's wives
  • Yulin Alliance young lord
  • Yulin Alliance Elders
  • Barbarian Warlord


  • In the timeline that his descendant, Director Cheon came from, the archives of history stated that Cheon Yeo Woon was titled the Slashing Demon Emperor and was the 24th Lord of the Demonic Cult. Likely due to the number of limbs he has cut off. Yeo Woon felt that the name seemed familiar to him. He has the cruelest hands among all the previous lords. Even the reason for his title being created, without leaving a single person who offended him, their arms were cut off.
  • Blade God had stated that he fought a future version of Yeo Woon where he had the moniker of Demon God, and that the present Yeo Woon had just exceeded in power.
  • He had cut off the arms of nearly every one of his siblings except for Cheon Jongsum of the Poison Clan. He had destroyed the dantian of Jongsum instead.
  • While not directly cut himself, as Lord he ordered the surviving disbanded Six Clans to cut off the arm of his father's surviving wives.
  • His name was given to him by his grandfather Cheon Inji.
  • He already guaranteed Mun Ku as his first wife in Nano Machine but later acknowledged Wang Yogun as his second wife after Descent of the Demon God.