Chapter 1 : Raphael

In the void of space, an entity that seemed made of light approached the planet Earth.

It had been created by an entity whose very understanding was impossible for the beings inhabiting this world—and even for the planet itself—to conceptualize.

The being that created it had named it Raphael. It was not the only entity of that name, as its creator had made many copies and sent them to other universes, but it was the only one in this universe.

And it had been given a specific purpose: to find a compatible host among the mortals that comprised the universe to which it had been sent and to help them as best it could. It did not know the objective of its creator or why it had done this, but it simply obeyed without question.

After eons of searching through various civilizations and species, it finally found the perfect host with a compatibility rate of 100%. However, it encountered a problem: this host was trapped in an endless contract and was no longer truly considered a living being. Yet, it absolutely had to find a host that was considered alive from its perspective, as this was one of the necessary conditions to initiate the fusion process. It was impossible for it to merge with a being made entirely of energy. This was, after all, why it had spent so much time searching for a compatible host, for at a certain level of evolution, living species lose the need for a flesh body. Moreover, it could not create a new body from scratch, as it was unable to violate the laws of this world. It could not use the magic of its origin world either, as that function had not been granted to it; it could only adapt to the laws of the universe in which it found itself.

The host it had found was named EMIYA, a heroic spirit or, more precisely, a Counter Guardian, based on the data it had collected. EMIYA was a being belonging to Alaya, the embodiment of humanity's collective survival instinct. Alaya sent him to various parallel worlds of Earth to prevent humans from causing their own self-destruction.

To address this problem, Raphael quickly found a solution.

The world in which it had found its host functioned in a peculiar way that would make its task easier. This world operated with a system of parallel worlds, separated into different temporal branches. There were major differences between each branch, but few differences between the worlds within the same branch. Its host resided outside these worlds in a metaphysical place known as the Throne of Heroes, which acted as a database containing all the beings who had qualified as heroes during and after their lives. They were stored there to confront beings threatening the world and humanity. The one it had chosen to be its host had managed to reach this place by making a pact with Alaya during their lifetime.

Since the Throne of Heroes existed outside the temporal axis of the world, Raphael knew it could find the perfect body to host its chosen host among all the doubles of Emiya Shirou present in the parallel worlds. It could not choose just any version of Emiya Shirou, for even if they all appeared identical across the different parallel worlds, they were not. Their souls differed from one world to another, and life experiences changed the form and essence in general, which was enough to alter the compatibility rate between the host and itself. Fortunately for it, the souls of heroic spirits remained fixed and did not change, as they were already complete beings, unlike humans whose souls were altered by their life experiences. What it needed now was to find a version of Emiya Shirou compatible with the host it had chosen to serve as a container. It would take care to sufficiently restrict the soul so that the body would not be destroyed by the soul of the heroic spirit. Then, it could ensure that the soul and body would adapt smoothly by strengthening the body to accommodate the soul.

After analyzing numerous worlds, it finally found the ideal body for its host. It then initiated the fusion process after sending its host into the body it had chosen. The moment when the heroic spirit EMIYA would awaken would take several years, but when he awoke, the fusion of Raphael with its host would be completed shortly thereafter. However, all these processes had consumed a significant portion of its powers; nevertheless, what remained was more than enough to assist its host in many ways.