As dungeon-like treasure vaults started appearing throughout the land, more and more people began signing up as treasure hunters—risking their lives to obtain the vast riches and ancient relics inside. In the imperial capital of Zebrudia, the top hunter party is the Grieving Souls—a group of six childhood friends led by Krai Andrey, who is thought to be the strongest of them due to having a reputed wide array of skills.

However, Krai actually has no special talent. His accomplishments are actually the result of his friends being overpowered. Krai has repeatedly attempted to leave the party out of fear his lack of aptitudes would one day cause his companions' downfall. Nevertheless, everyone around Krai thinks differently, making him feel obligated to remain the group's leader.