When I Regressed, I Was an S-Rank Hidden Guide

After dying in misery following a lifetime of exploitation at an illegal guiding ring, Seo Yul is granted a second chance and returns to the past. To forge a new future, he approaches Cha Do-oon—a notoriously volatile S-rank Esper believed impossible to guide—and offers his services, claiming his C-rank ability is surprisingly versatile. But during their matching test, he receives the shock of his life: his rank is not C, but a staggeringly rare 'Hidden S-rank.' Now, Seo Yul must uncover the secret trigger behind his power if he ever hopes to stand as a true equal beside the dangerous Esper rewriting his destiny.