Rock is transported to the world of *DanMachi*, becoming a slave to the Icarus Familia. Awakening his "Dimensional Simulation System," he transforms into a Dead Apostle Magician in the Type-Moon world, wreaking havoc in the Fuyuki Holy Grail War. Returning to Orario, he inherits five hundred years of the Makiri family's wealth, becoming a being that straddles the line between humans and vampires. When the swordswoman Ais delivers fragments of a broken sword stained with divine blood, the "Reality Simulation" finally activates—Rock discovers that he seems to have left traces in the "Greatest Evil Incident" seven years prior. Now, wielding the power of the Astrea Familia in his left hand and gripping the blade of revenge in his right, he embarks on a forbidden journey of absorbing divine blood and simulating sainthood in the labyrinthine city where gods roam.