While I have lots of ideas on my own, you help shape this story! What things do you want to see as the monsters interact with human society?
Also, I think I can get the Undertale cast relatively to have IC reactions. My problem is the word-for-word dialogue. Send help.
The monsters march down the mountain. An assortment of suitcases, travel packs, and wagons trail behind them.
While their steps are loud, most voices are hush. They are too amazed to speak.
The small creatures (and a lone ungulate) that inhabit Mt. Ebott watch the strange scene from a distance. The monster's trail is long and narrow: Around a mile long, including the wagons taking up the extra space. Almost a thousand monsters admire the wildlife as they trudge along to their destination: The city within view of Mount Ebott. The sky-scrapers show the way; and indicate a dramatic change from what it once was. The fort-village that once sealed them away and guarded over them would now be the place that reintroduces them to life above ground.
And humanity.
Guards escort the front of the line, and guard the rest. Conversing with people, ensuring the path is clear of large rocks and dangerous animals. Harmful plants had long since been moved aside when they picked out the best trail days before.
Undyne is not with them. Undyne hadn't even played a part in choosing the best path, outside of some small agreements with Asgore. She was busy serving as Frisk's official guard for their mission: Telling Humanity About Monsters. Asgore was absolutely terrible with names. He hadn't even spelled T.H.E.M right.
Her second-in-command takes her place, but not really. Though technically her regent, they aren't nearly as involved in the planning of this project as Undyne would've been. The entire Royal Guard is taking direct orders from Asgore on a group & individual basis. Normally, they would be taking orders from Undyne; who may or may not have been given orders by Asgore. The second-in-command focuses more on keeping everyone in line and ensuring that their soldiers are following Asgore's orders, rather than their own.
Speaking of, our King Asgore shepherds from the back. Duty suggests he do from the front, but he really wants to take a lower role. This way, he ensures there are no stragglers while his army does the rest; and he doesn't have to act like a leader.
He is chatting with Gerson and a family from Snowdin. The old tortoise was enjoying the sunlight and walking slow from both age and as a racial attribute. Asgore was happy to see him again; a fellow comrade in that he had lived Aboveground once before.
The family, on the other paw, had to travel slow due to their disabled child. In spite of this, they gave the kid a small wagon to pull. The wagon has a strap instead of a lever, which the child holds in their mouth like a bit.
Asgore is telling the family about how this band of pilgrims came to be. He has just finished explaining how some monsters and The Human witnessed The First Dawn since being forced Underground. He moves on to what he did after that incredible experience.