In a fantasy world governed by RPG-like rules, magic points are the essential currency for any adventurer. Lent is a young man with a unique Gift that allows him to loan his own magic points to others, making him an invaluable asset. He is a member of a rising party of heroes known as the Skypiercers. By generously providing them with his MP, Lent enables his companions to grow into formidable warriors. However, once they have reached the peak of their power, they deem him useless and promptly expel him from the group.

Humiliated and furious over his betrayal, Lent discovers a hidden power within his own Gift. He is no longer limited to simply giving away his magic; he now has the ability to forcibly reclaim every last point he has ever loaned, and with interest. Accompanied by an adorable yet cunning support fairy who acts as his partner, Lent embraces his new role as a magical repo man. He sets out on a quest for revenge against his former party members, determined to collect his magical debt by draining them of the very power he helped them build, all while using the recovered magic to become the strongest adventurer in the world.