Creating a Hidden Ending

After witnessing the ending of the game 'Regressing D-Rank Hunter,' Yeon Seon-woo wakes up to an unfamiliar ceiling and realizes he's possessed an extra character who never even appeared in the game. While searching for a way to return to the real world, he gets kidnapped by the protagonist he absolutely wanted to avoid—Lee Je-hee, an S-rank hunter and infinite regressor. Turns out, Je-hee wants the 'mentalist' Seon-woo's help with his insomnia. Though 'help' is hardly the right word for someone whose mind seems broken from endless regression. Under constant threats veiled as jokes, Seon-woo ends up signing an exclusive supporter—no, exclusive slave contract with Je-hee, getting summoned at all hours through a servant ring. Devastating beauty with a personality to match! Can Yeon Seon-woo escape his 'master' and return to his original world?