[[ Alrighty, hi! Brit here introducing my Undertale fanfic (my first one I've really written, and it's planned to be long-term, slow burn kind of thing). I'm gonna just layout some information here, at the beginning, so that there aren't any surprises.
This is NOT a reader insert, or a self-insert. This has an OC that is female. (The Pic for this fic is actually her pic that I drew, so… If you were wondering what she looks like, there ya go.) It's Sans/OC. If you don't like that, then please, go ahead and don't read. It won't hurt my feelings any if this doesn't fit your tastes.
Other pairings are Undyne/Alphys, eventual Toriel/Asgore… Some others will be added/introduced later.
Frisk in this is written without a particular gender (I use 'they' pronouns), and is mute. He uses sign-language.
Souls play a BIG part in this, as it'll come into play later. (Not soul-sex, necessarily. It takes part in more than just sexual relationships, as it's an important part of monster culture).
I hope you enjoy this! Please, feel free to leave me comments to tell me if I make any mistakes with keeping perspective (using 'you'… I don't mean to, it just happens *sobs*), spelling errors, or to tell me what you think. Thanks again!
]]

Daily life had taken a drastic turn the day that Monsters broke to the surface. By some unforeseen amount of power, the barrier that humanity had all but forgotten crumbled, and shattered, leaving an empty doorway from the 'Underground' to 'Aboveground'. Then, just like that, the world was thrown back into the 1950's. Signs proclaiming businesses as 'human only', or 'monsters forbidden', popped up as if overnight, scattering like seeds that quickly sprung forth a seething hatred. Not all of humanity had lost its senses, but, when you look from the outside, the bad often overshadows the good. The bad apples stand out more in a bunch, as they say.

A meeting had been called, and the Ambassador, who was nothing more than a child, accompanied by a cast of six monsters, asked to work out an arrangement. And as such, one was made. Mt. Ebott loomed overhead as a town was built, small, but peaceful. Many monsters were unhappy that they were being 'segregated' into a single location like that, but their Queen admonished their complaints quietly, reminding them that it was 'improvement'.

It was all about the baby steps.

Slowly, there came to be humans who asked to move into the 'Monster Town' and, at first, there were a few monsters who refused, who said that if they weren't allowed into their towns, then humans weren't allowed into theirs. Naturally, the King and Queen did not share their views and, although they were a bit hesitant, they welcomed people with open arms. Thus began the first signs of co-habitation between monsters and humans. The funding for their construction of buildings was limited, since many of the people in control of the funds weren't exactly Pro-Monster. But they made due with what they had. Apartment-like buildings were risen, and businesses took form, and soon enough, it became a quaint little town. From within the town's boundaries, you wouldn't have ever been able to tell that there was any discourse within the world.

After a while with 'no incidents', people began to assemble movements pushing for equality laws. It was so familiar to the times of old, of bigoted, narrow-minded people refusing rights to people who had done nothing but exist, who deserved to be treated the same as humans. Their fear was well-founded, in a way. Beings with magical powers suddenly erupting from underground, asking for places to stay, food to eat, jobs to have… it would surely put a strain on the economy. But politics is as politics does, and, eventually, laws were written and founded. The biggest and initial trial was the one that stated that those from the Underground were American citizens. The monsters were overjoyed, and the trial was highly celebrated. This meant the coming of many greater things. They'd have the right to open businesses for tourism, and they could earn for themselves, instead of having to live off of the money of the state.

Not everybody was happy with the outcome. Many humans held protests (not always quite as peaceful as they were letting on), and there were instances of attacks. The state, however, refused to accept them as 'hate crimes', so little ended up happening to those accused. A slap on the wrist, and they were set free to continue their racism and hatred. But those in charge of the little town tries its best to keep resentment from boiling too high, and instills an amount of hope in those monsters that they will eventually have equality.

Two years later, there is a tentative peace.

Talk of a school being built in the 'Monster Town', more formally known as Taobh, sent the surrounding towns buzzing with rumors and conversation. Many worried what sorts of things they would teach there, and conspiracies started to float around that the monsters were planning on teaching their young how to devour human children. Ridiculous ideas that should have been brushed aside as the preposterous rumors they were, but several humans actually began to believe it. It was such that the Queen found herself visiting the law office in the nearby town of Tristin on a weekly basis, pleading her case and trying to work with the lawyers to get her a teaching license. It was tentative, but a building was being constructed already, in preparation for the school being founded. She had hope.

Word got out, and a few humans started looking into trying to secure a job there, those who needed a way to escape the place they currently were, or those who wanted to do right by monsters where several of their own kind were doing such wrong. They were just as hopeful as the monsters, because the monster children were having to attend human schools in the meantime. (It was either that, or they didn't go at all, which many parents seemed to prefer, human and monster alike.) Toriel worked hard and, after many, many hours of deliberation, was granted permission to start schooling the monster children. Frisk, however, as a human, had to continue attending the large public school in Tristin. It wasn't ideal, and she was taking online college courses to get her teaching degree so that maybe, hopefully, she could convince them to let her teach anyone. As of now, though, that dream seems a bit further off. But she's happy with what she's achieved, and so are many of the monsters in Taobh.

It's a start.