Leaving behind only a single key, Kim Woojoo's father, a renowned web novel author known for his 'Overpowered MC' stories, passed away. Ten years later, a virtual reality game called 'The Other World,' based on one of his works, becomes a place where people can make a living or even strike it rich. Kim Woojoo has been living a tough life with no special advantages. By chance, he discovers that the key, a keepsake from his father, is being traded at a high price. He decides to use the key to open a limited edition book in his father's study and receives a special gift from the game. Accepting the gift, Woojoo encounters the Great Demon King Lucia, a character from his father's web novel. Lucia grants Woojoo incredible abilities, but the power is so overwhelming that Woojoo struggles to complete even simple daily quests. After much thought, Woojoo decides to eliminate the source of his power, the Demon King, by bringing in another character, Killer Zero. However, his actions draw the attention of Jason, a powerful player in 'The Another World,' who comes to confront him. Will Woojoo be able to face the strongest characters in the game, the ultimate beings from his father's web novel?