Hero? I'm just here to borrow power

The final battle unfolds in Shinjuku, a demonic realm beyond human reach, defined by an endless clash of swords and slashes. Baiye stands before the two Su Nuo, confronting a subspecies of fantasy materialization known as "Underlying Marble," a grand magic capable of rewriting reality through collision with the realm of birth. Above Tokyo’s Red Well, Nidhogg—a planetary life form and black dragon—unleashes his power of "Annihilation" against humanity. Yet, the supreme light emitted by White Night ultimately strikes the Black Dragon from the sky, for standing before the Black King was a true giant of light. Meanwhile, Chaldea, the organization dedicated to ensuring humanity’s survival, faces an overwhelming manifestation of human evil. Fujimaru Ritsuka petitions the Counter Force to summon a Heroic Spirit capable of halting this great calamity. The response is not a Grand Servant, but a man named Byakuya. His story begins in the snowy cities of America, amidst a Holy Grail War where the real and the...