As is common knowledge in the Moonlit World, mages seek to hone their magecraft in order to reach the Root and obtain the True Magic. However, the Root is not the only goal of magecraft. Legend tells of the existence of a colossal, mechanized god of almighty power. A divine being existing outside time and space, capable of observing and overseeing countless possibilities and timelines of our world. So powerful is this deity that it has concluded that any interference on its part would cause massive, irreparable harm on our world, regardless of its noble intent. Therefore, it has remained on the sidelines, ever watching our past, present and future play out naturally.

This being is known as Bastion, The Flawless One....and it was the Ullser family that were the first and only mages to have succeeded in reaching this glorious fusion of magic and technology.

Reginald, prefers to be called Reggie, Ullser comes from a relatively old line of secretive mages, the origins of the family dating back to the birth of the Industrial Revolution. As a family that began right as Mystery began to decline, this peculiar group of mages uses modern technology alongside their magecraft, as way to augment and fine-tune their abilities. Unsurprisingly, this earned the family a rather low reputation of not being "real mages" among the more ancient and traditional mage families. The dreams of the Ullser family were mocked and ridiculed, regarded as a "wild goose chase for a thing that doesn't exist."

However, through decades and centuries of research, failures, trials and bloody wars, the Ullsers did reach their goal: Bastion. Upon learning and understanding this enigmatic god, the family made a wise decision. Realizing the catastrophic ruin that would come from Bastion's mere presence in the world, the Ullsers would go into hiding, ensuring the existence of Bastion would never see the light of day. The mage world would go on to assume the Ullsers had reached the end of their magecraft and simply faded into obscurity.

Years later, on rare happenstance, a woman, by the name of Ritsuka Fujimaru, sent a letter of invitation to the Ullsers, offering one of their number to be a member of the Security Organization, Chaldea. Not believing this to be mere coincidence, the family turned to Bastion for guidence.....and were revealed a grim vision:

A dark fate was set to befall on Humanity, in all timelines. One that, if not met and deterred, would require Bastion's interference.

Knowing that such an occurrence would spell disaster, the Ullsers would send their oldest son, Reginald. Kind yet guarded, crude yet wise beyond his years, the 20 year old was the most prospective of his generation, as well as the most talented. Hopefully, his talents and skills, along with the teachings of Bastion, will be of great help in averting this looming crisis.

Medusa and her sisters were born from the wishes of mankind for ideal idols, the embodiment of the yearning hearts of men. As "perfect goddesses", their "divine essence" was to remain the same from the moment of their creation to their destruction. Medusa was an exception who was a failure from birth, growing older over time. Though they should have all been copies, or even as close as clones, resulting from the deification of the same phenomenon, a mistake in her birth or something of deeper significance caused her to be copied imperfectly. While she did not embody "forever young and immortal", she gained abilities in compensation compared to her sisters' inability to even care for themselves. With divine powers, her Mystic Eyes, indispensable in protecting her sisters who could not live in the world on their own, this caused the previously united sisters to become three separate individuals. Although Medusa was different from the start, even the other two showed irregularities, their sadistic nature, from interacting with her.[8]

She was originally considered to be a princess loved by humans, but Athena, jealous of their beauty, cursed Medusa alone, taking away her "faith from each and every person" and exiling her to the Shapeless Isle. Their love for her turned to hatred, and she was banished by those who had adored her. The island had nothing to offer compared to her days of luxury, and she prayed that none of the humans that now frightened her with their unwarranted resentment would tread on the island. Weeping in loneliness, she had no idea as to her sin that forced her to be exiled. Although her sisters were not affected and still greatly loved, they too accompanied her there out of caring for their younger sister. She was happy even on the barren island due to their company, and only had to fear the coming humans.[8]

While they became rumored as monsters, her sisters were still revered by nearby men, while she was feared as a monster. Humans sought to kill that which had been branded as a monster and take away the goddesses, and after they began to also target her sisters, she decided to protect them while taking her revenge on the humans. Although littered with statues that had been warriors, they were harmonious for a time on the island, at one point receiving her Pegasus from Poseidon. Though bullied by her sisters daily, she simply moved about the island on days humans did not appear, hoping for the peace to continue. Repaying them in the same manner as they treated her, she killed many humans, simply hoping to be left alone on the only place she could exist with the company of her sisters.

Though she was protecting them from the foolish humans who sought their own deaths, her sisters warned her not to take pleasure in killing them. Using her eyes that were only a deterrent to sow terror in humans, she began to experiment in ways of killing them more quickly. Deciding to become a trap against those who would take her sisters, even they who had always been full of joy began to fear her after she started drinking their blood instead of simply petrifying them. The humans continued to journey the island no matter the infamy surrounding her, and she eventually became too ashamed of her slowly disfiguring self to appear before her sisters. Leaving them, she once again found herself alone, hungering for new sacrifices to replace her sadness and loneliness.

She grew into the Gorgon each day as her body, heart, and very being decayed, all backed by the thought of becoming stronger for the sake of protecting her sisters. Even that reached a point where her sisters instead became nuisances who were intruding upon her lair. They appeared before her after her full descent into a monster, lamenting that they had not asked for her protection and were just letting her enjoy what had seemed fun to her. Saddened by her state, they sacrificed themselves to the Gorgon because the sister who protected them was no longer there. Consumed by countless snakes without any trace of joy or sadness, they were ground into pulp and absorbed into the beast while still alive. Without leaving a trace, they became its flesh and blood, and it continued to thrive as the Gorgon sisters became monsters of nightmares and legends.

The Gorgon's notoriety continued until Perseus decided to bring back its head for his own fame. Granted five Noble Phantasms, he boldly traveled to the Shapeless Isle without any hesitation, only realizing his folly upon seeing the state of the island. He despaired upon encountering it, having decided that there is no victory to be found against the demon god, with his Noble Phantasms only acting as lifesaving equipment in the best scenario. Avoiding her gaze by focusing on his Mirror shield, he desperately fought to survive. Tired of toying with him, it used Breaker Gorgon, and he used the only possible method of defeating it, using Kibisis to have it encage itself.

Reversing the nightmare of the Bounded Field upon it, it suffered as Medusa as the nightmare reflected upon it instead of Perseus. While it was a "nightmare beyond nightmares", it was not an evil vision that caused excruciating pain, but a pleasant dream of her sisters, paralyzing her with the joy of seeing those she thought she would never again meet. Despairing upon the reflection of itself from when it was still self-aware, this allowed Perseus to have his single counterattack, severing its head with Harpe. The monster, out of its own will, became Medusa again and let itself be struck down. Perseus used Kibisis to hold its head, later going on to become a successful hero.

Hailing from long line of secretive yet clever mages, Quill Gellers is the youngest son of the Gellers family, a mage group dating back to the Age of Gods in Ancient Greece. Always keeping to themselves, the family do not have ties to any of the factions in the Moonlit World, be it the Atlas Institute, The Wandering Sea or the Clock Tower. As such, any who do encounter a Gellers are met with uncanny wit, esoteric magecraft and modern worldviews. Quill is no exception and when the Chaldea Security Organization offer a slot to the family, it was Quill who was sent to fill the need.

The young 20-year old would've never have guessed the adventure he would undergo for accepting the offer...