The Catacombs are labyrinths connected to suddenly appearing gates, where only players awakened with special skills can fight the enemies within to protect humanity. Sota Sezaki, born to player parents, fails to awaken and is scorned as a weirdo because he can see spirits. After entering a gate with his childhood friend, he is nearly killed by the strongest boss, the Queen Spider, and finally awakens a unique skill that lets him inherit the abilities of the dead by resolving their lingering regrets. Guided by the wandering soul of his fallen father, a legendary fire mage, Sota challenges the Catacombs to become the strongest player.