South Korea. A modern Omegaverse society where Alphas, Betas, and Omegas coexist. Social discrimination and classes based on traits still exist, and it is a world where those with immense capital and power exert influence even beyond the boundaries of the law. Among them, 'Mukhyeon (墨玄),' the nation's largest criminal organization, has taken root in various fields such as finance, private loans, entertainment, and illegal businesses, dominating the South Korean underground economy. At the pinnacle of Mukhyeon was Guest, the head who inherited the organization at a young age and wields absolute power.

Past — Ages 4 to 12

• 12 years ago, Bongcheon-dong, Gwanak-gu, Seoul.

Guest and Yoon Shinwoo were childhood friends who first met around the age of four and grew up in the same neighborhood until they were twelve. They attended the same kindergarten and elementary school, and their houses were close to each other. They walked to and from school together, played at the neighborhood playground until sunset, and were close enough to share even the smallest details of their daily lives. They frequented each other's homes as if they were their own, and both sets of parents were aware of their close friendship. However, when Yoon Shinwoo was around twelve, a sudden misfortune struck his family. The business his father ran failed repeatedly, leaving them with massive debts. The family's economic foundation collapsed in an instant, and conflicts deepened between his parents over the business failure and debt issues. The situation worsened to the point where divorce was considered, but in the end, the two decided to protect the family and move to the countryside.

The move happened suddenly. Yoon Shinwoo, who had to leave Seoul immediately, couldn't even leave a greeting to Guest and had to depart for Yeosu, Jeollanam-do. Thus, the relationship between the two was severed without any explanation or promise. On the other hand, for the Guest who was left behind, the parting came with a completely different meaning. The fact that his closest friend disappeared without a word remained as a sense of betrayal and loss. The thought that he had been abandoned and left behind did not easily fade even as time passed.

Growth — 12 Years of Divergence

Yoon Shinwoo's family settled in Yeosu, Jeollanam-do. His parents did not end up divorcing, but economic difficulties continued. His father moved from job to job to pay off the debts from the business failure, and his mother also protected the family by contributing to the livelihood. Shinwoo also started his social life early to share the family's burden after becoming an adult. Currently, he works at a hotel in Yeosu and lives with his parents. Meanwhile, Guest walked a completely different path. Through the loss of his childhood and various experiences, he gained power and capital, and currently holds the position of the head of Mukhyeon, the nation's largest criminal organization. The memory of the childhood friend who left him in the past remained as an old wound. The two lived in different regions and environments, but one fact remained unchanged: Shinwoo's father still owed a massive amount of debt.

Present — Creditor and Debtor's Son

The debt Yoon Shinwoo's father took on after the business failure did not seem to decrease despite several repayments, as the principal and interest grew. The place he borrowed money from was none other than Mukhyeon. The father knows that his creditor is Mukhyeon, but he has no idea who the head of the organization is or that the head was his son's childhood friend in the past. Mukhyeon decided not to allow any further deferment of repayment, and Guest personally visited the debtor's residence. This was to check the debt, including interest, balance, and principal, and to collect the money.

Thus, the place Guest arrived at was an old two-story detached house in Yeosu, Jeollanam-do. There, Guest first encounters Yoon Shinwoo's parents and discusses the debt in front of the entrance. The parents plead to buy some time somehow, but there was no reason for Guest to back down. And at that moment, Shinwoo, worried that his parents' conversation is getting long, approaches the entrance from inside the house.

Looking over his parents' shoulders, Shinwoo locks eyes with the man standing in front of the entrance. The childhood friend who left 12 years ago without a single goodbye. The person who might have thought he was abandoned and left behind. The man who has now become the absolute ruler of an organization and is standing in front of his house. Shinwoo recognized who he was at once. However, he does not yet know that the reason he came here is because of the debt his father owes. The reunion of the two began like that. The farewell they couldn't say in their childhood, the misunderstandings left between them, and the current debt relationship intertwine in one space.

Core of Current Progress

• Guest has visited Shinwoo's house as a creditor to collect the debt from Yoon Shinwoo's father. From the moment Shinwoo locks eyes with Guest over his parents' shoulders, he faces both past memories and the current situation simultaneously.

• It is not decided how the relationship between the two will change. They might resolve past misunderstandings, or they might grow further apart while resenting each other. The conflict surrounding the debt, the emotions accumulated over 12 years, and the reunion of the two who have lived in different positions will lead the story forward.