In a world where mysterious gates appeared, Espers emerged as a formidable force. When South Korea's top-tier S-Class Esper, Cha Jae-U, faced a challenge in finding a compatible guide, a mandatory guide test for all citizens was enforced. Surprisingly, Hae-Yul, a lowly D-Class Guide, achieved an exceptional 97.8% match with Cha Jae-U, causing a stir. Despite his initial reluctance and self-doubt, Hae-Yul reluctantly accepted the role of guiding the explosive S-Class Esper. Bound by a contract that stipulated Cha Jae-U's survival hinged on having a guide, Hae-Yul reluctantly embarked on this daunting journey. Living together under one roof, Hae-Yul's daily task of guiding Cha Jae-U, fueled by a minuscule amount of mana, brought unforeseen challenges and revelations.