Kaiju Number 9 had lost, his core was shattered and his body would be used to create weaponry. But instead of dying, he instead found himself in a world with auras, semblances, dust which, while battle hardened against the creature of grimm, was in no way prepared for a kaiju attack... how fortunate, a world where he could experiment with humans with no risk of death.

In a world full of giant monsters known as Kaiju, young Ben Tennyson finds himself teaming up with a man who has the ability to transform into a Kaiju. Together, the two will rise through the ranks of the Defense Force and stop all of the evil Kaiju for good.

After Garou along with a couple of heroes and civilians got brought into another world, they find themselves still having to deal with Monsters that are called Kaijus, during there stay, they manage to help the people the same way they do things in there world, also Garou gets to the Strongest Monster in this world and that during his stay, he also helps guide Kaiju number 8.