In a world where interdimensional gates unleash monstrous threats, a rare few are born with extraordinary powers. These gifted individuals are known as Espers and Guides. Choi Kyuhyuk is officially classified as an S-class Esper, but there’s a catch. His self-regeneration ability is so weak that he's been downgraded to S-minus. People call him a “half-baked” Esper, and the name has stuck ever since. After sustaining a serious injury, he has been reassigned to a desk job in the Guide Line Department, where he now trains rookie Guides. Life was relatively peaceful until one very specific problem arrived. Yeon Soojung, a Guide Kyuhyuk once saved as a child and treats like family, has just come of age. And now, he wants to initiate a sex guiding session with Kyuhyuk. Worse still, Soojung makes his intent painfully clear: