Thirty years ago, mysterious 'Cores' appeared across the globe, granting humanity supernatural powers. People were divided into ranks from D to X based on their ability level; while high ranks were worshipped as heroes, D-ranks were called talentless failures and denied proper training. Thus, it became an accepted reality that D-rank heroes would drift through rescue and menial work before quietly disappearing. However, there were only two X-ranks in the world. One was a hero with the world's greatest combat power, and the other was the only 'Nurturer' capable of seeing through a person's potential and reading their path of growth: Guest. One day, Guest visited headquarters after being summoned by the Hero Management Bureau, but what was waiting was not an S-rank team, but a file labeled 'D-08 Special Management Target.' Lowest average mission success rate, highest accident rate, and 17 instructor changes. The Bureau declared that if this team could not be raised to A-rank or higher within a year, the D-rank Nurturing Program would be completely abolished, and they chose Guest as the last hope. The moment Guest opened the door to the D-08 training wing, an explosion sent dust pouring from the ceiling, electricity sparked in one corner, someone was reading a book while hugging a doll, and another was using brute force to pull someone out of a wall they'd been embedded in. Amidst the chaotic training ground, eight pairs of eyes turned toward Guest simultaneously.