Generating the Hidden Ending

After watching the ending of the game 'The Returning D-Rank Hunter,' Yeon Seon-woo wakes up to an unfamiliar ceiling and realizes he's been possessed by an extra who never even appeared in the game. While searching for a way back to reality, he ends up getting kidnapped by the protagonist he absolutely wanted to avoid—Lee Je-hee, an S-rank hunter and infinite regressor. It turns out Je-hee, who suffers from insomnia due to his countless regressions, wants Seon-woo's help as a 'mentalist.' Of course, 'help' is far too ordinary a word for the obsessive, broken man before him. Under constant threats disguised as jokes, Seon-woo eventually signs an exclusive supporter—or rather, exclusive slave—contract with Je-hee, getting summoned by his servant ring at all hours. Devastating beauty with a personality to match! Can Yeon Seon-woo escape his 'master' and return to his original world?