Luo Shu arrives in a modern world blending Japanese pop culture with hidden mysticism, armed with a mysterious system that converts faith and conviction into Divine Power. Posing as an enigmatic mage in traditional robes, he sets up a fortune-telling stall in a bustling park, but his true goal is far grander: to reconstruct the legendary Holy Grail War. Using his ability to read confidential data, lifespans, and fate trajectories, he effortlessly astounds locals, from idol trainees like Hoshino Ai to the prestigious Yukinoshita sisters.

By revealing dark futures and offering miraculous solutions involving glowing gemstones and divine visions, Luo Shu gathers the belief necessary to fuel his ambitions. As rumors of his supernatural prowess spread, he begins to manipulate the strings of destiny, summoning heroic spirits and preparing the stage for a global conflict that will blur the lines between reality and myth. With every converted skeptic, his power grows, turning a simple con artist's facade into a genuine gateway for gods and monsters to enter the human realm.