Endowed with boundless power and an innate knack for channeling borrowed strength, coupled with his mastery in martial arts from a tender age, Mubong Park's childhood was steeped in opulence and privilege. Throughout his life, accolades showered upon Mubong, hailed as a 'once-in-a-millennium talent' [2], destined to reshape the world and ascend to kingship, hailed as humanity's savior and a prodigious rarity. Such praise trailed him into adulthood.
​
At the age of 18, Mubong achieved a remarkable feat by joining 'THE SIX'—an elite cadre comprising the world's most formidable martial artists and BP users. His induction at such a youthful age etched his name in history as the youngest member ever to join 'THE SIX'. Yet, amidst a confrontation with one of the greatest threats ever faced by the group, Jin Taejin, Mubong suffered a humiliating defeat, marked by a permanent 'X'-shaped scar on his forehead.
This setback shattered the faith of his family and the purported 'Prophets' and 'Shamans,' casting doubt not only upon Mubong but also upon the adulation they had showered upon him. Consequently, Mubong's confidence waned, and he began questioning his own strength, grappling with self-doubt and a sense of inadequacy.
​
One fateful day, stirred by a dream, Mubong crossed paths with a young woman of similar age, exuding hatred toward society. Captivated by her demeanor, Mubong trailed her, observing her interactions throughout the day. After several encounters, he confronted the young woman, Mansuk, and delved into her tumultuous past, marred by self-loathing and the burden of familial expectations casting her as a savior. Recognizing parallels in their struggles with self-worth and upbringing, Mubong seized the opportunity to connect with Mansuk on a deeper level. With his characteristic candor, he confronted her, drawing parallels between her and the individuals she despised, including himself. Yet, he also pointed out the existence of another breed of humanity, exemplified by her brother, Mandeok. This revelation sparked a newfound sense of confidence in both Mubong and Mansuk. Unbeknownst to him, this pivotal moment served as the catalyst for their blossoming romance, as they both discovered a profound connection and fell deeply in love.
​
Mubong's life gradually started looking up. He began to let go of the embarrassment from his past defeat and instead focused on understanding the concept of 'True Strength,' using Mandeok as his inspiration. He wanted both Mansuk and himself to build confidence, mirroring the resilience Mandeok displayed despite his fragile body and weak immune system. Unaware of how these siblings would impact his life, Mubong found joy again, laughing, smiling, and bonding with Mansuk and Mandeok. He joined Mandeok in helping those in need, serving food to the hungry, and enjoyed romantic outings with Mansuk. It was during one of these dates that Mubong acquired his signature red Hawaiian shirt.
During a date with Mansuk, Mubong was asked why he changed his name. His response was straightforward: he found his old name outdated and didn't want to be stuck with a name given by 'a bunch of old farts.' So, he chose the name Mujin. When questioned about its meaning, Mujin admitted he didn't know. It was Mansuk who provided a definition: 'Inexhaustible, Unlimited, Infinite.' This newfound name became Mujin's driving force. Every day, he pushed himself to his limits, disregarding others' opinions about his strength and realizing that their judgments didn't define him. He came to the conclusion that he didn't need to be perfect.
One day, while walking in an alley, Mujin encountered three bishops from NOX. Boldly insulting them, Mujin found himself quickly overpowered by one of the bishops, who demanded information about 'Jecheondaesong', and warned him about triggering a vicious cycle that would last thousands of years. Feeling threatened and confused, Mujin retaliated and managed to escape without being pursued. Rushing to the church where Mansuk and Mandeok lived, Mujin was greeted by the sight of Mandeok standing alongside the supposed Maitreya, which later reveals himself to be Beelzebub after being called out by Mansuk.
​
Amidst the ensuing chaos, Mubong learns of 'The Key,' a mysterious element of significance. He attempts to confront Beelzebub in combat but finds his attacks ineffective against the deity's overwhelming power. In a drastic move, Mubong causes both himself and Beelzebub to crash into India, hoping to gain an advantage in the unfamiliar terrain. Despite their relocation, Beelzebub continues his relentless assault, posing a grave threat to Mansuk, Mandeok, and others who find themselves caught in the conflict. Mubong, fueled by a fervent prayer, unleashes a potent attack amplified by a national treasure, severely weakening Beelzebub. However, in a tragic turn of events, Beelzebub strikes back with lethal force, endangering Mubong's life. In a selfless act of sacrifice, Mansuk intervenes and takes the fatal blow meant for Mubong, leaving him devastated by her loss and profoundly affected by her final words- "I hate humans".
​
Over the span of 34 years, Mubong meticulously plotted his vengeance against the Gods for their betrayal. He employed deceit, manipulation, and even murder to further his agenda. Amidst his schemes, he delved into research to uncover the mysteries of the 'Key' and how to break the 'Taboo' imposed upon humanity.
He regularly destroyed NOX branches and rescued a child, later to be known as Ultio R. During his pursuit, Mubong also encountered a teenage girl orphaned by tragedy. Moved by pity, he took her under his wing, gradually becoming consumed by his quest for revenge. To further his goals, he orchestrated a global fighting tournament, masquerading as a competition for 'the ultimate prize' while secretly aiming to uncover the Key and shatter the Taboo.
It took 17 years before Mubong's plans bore fruit, culminating in the discovery of the Key within Park Ilpyo. However, his path intersected unexpectedly with Jin Mori, the legendary Monkey King, Jecheondaesong, whose memories were sealed. Thus began the intertwined tale of two Gods, similar yet distinct, as their destinies collided.
