Archive of Our Own ^beta

Chapter Text

The first time Sans remembers something different is as he's sitting on the floor, stacks of books scattered near haphazardly around him as he focuses on the words printed onto the papers before him.

M onsters have been trapped for a century and a half by now. In order to break the barrier which keeps us locked underground, we will need the power of seven human souls that match with those who cast the spell.

King Asgore, is kind to a fault. Despite the actions of the humans against our own, he would prefer not to take a life of an innocent. In the case that any human who falls below is a criminal to monsterkind, they will be captured and harvested for their soul.

However, our king has decided that there may be other non-violent methods to break the barrier. Which is why our team has been established to research the effects of certain matter on every subject we are permitted to use.

"King...Asgore." Sans mouths, bringing a hand (are his fingers supposed to look that way?) up to his teeth. With a faint clack of bone against bone, he mouths the name again.

It sounds familiar. He thinks to himself, hunching up in his oversized sweater. Did he hear that name somewhere?

"I prefer Asgore to Toriel."

"What?! But GOAT MOM!"

"Yeah, but Goat DAD."

Who prefers Asgore to Toriel? Who's Toriel? He reaches out to trace the words on paper, bone furrowing above his eyesss—sockets. He doesn't have eyes like humans do, only eyelights and eyesockets.

"Goat Dad."

"Goat Dad," Sans mumbles.

Who prefers Asgore to Toriel?

"Ugh. Really, you..."

He does.

Sans prefers Asgore to Toriel.

---

The second time Sans remembers something different is when he stands beside his father—mother— creator, Doctor W.D. Gaster.

They're running(?) an experiment and Sans clutches a clipboard in his small, bony hands, watching the giant glass tube that towers over even Gaster. Gaster told him that he and the glass tube are separate from his team's main one. That him and the tube are independent projects.

Gaster's fingers, phalanges, touch a black screen set in front of the glass tube filled with water. Sans can see different tubes that go into the glass container, but he can't see what or who's inside. The water's not clear enough for it.

The black screen comes to life at the press of bone, like a tablet or phone.

Sans nearly frowns, confused. What's a tablet, what's a phone? They're clearly important if they remind him of the device that Gaster is handling right now.

The screen flickers to show numbers and symbols that Sans is too young to comprehend, before turning to a view that looks like what's inside the water-filled container.

It's a child, or what seems to be one.

It's curled up in a fetal position with one of the metal tubes plugged into the back of its skull.

A skeleton child.

From what he can see, its skull is a little longer and narrower than his, more like Gaster's. Its bones are small, like they'd break in half with just a squeeze. Twigs.

It doesn't look nearly as developed as its supposed to be if it wants to walk around.

Sans glances up at Gaster, startled to see the older skeleton eyeing him. His fath— creator's eyelights flick to the screen, then back at him, like he's considering something?

What are you thinking about, Gaster? He wonders.

A faint static fills his head, and he recognizes that his creator is about to speak.

"This is going to be your little sibling."

Little...sibling. He's going to be a big brother?

"Here's your little nephew!"

"Oh god I feel old."

That's wrong, he's going to have a sibling, not a nephew. And he's still in stripes, not old.

Sans stares at the recording on the screen for a brief moment, before tearing his gaze away to ask curiously. "Boy?" Gaster lets out a small huff that makes him wonder why; they're both skeletons, why do they simulate breathing? They don't have lungs, they don't need oxygen—

What's oxygen? Don't lungs belong to humans? What do they have to do with skeletons?

"This one will be whatever they want to be." He blinks back to reality at the quiet voice and static.

So it'll either be a girl or a boy. Why is Gaster letting him see all this?

Sans voices his question.

Gaster lays a hand on the tube, like he's trying to feel for something. Shockingly, his usually intense gaze softens when he makes eye contact with him. The static is a constant, pleasant buzz.

"You will be who cares for this one, otherwise you'll be lonely," His creator tells him. "I may not always be there, so I'm giving you this one to keep you company."

"Alright. I'm leaving you my spawn to keep you company."

"I'm going to break him in half though."

"You'll be fine!"

"He's going to break like a twig if you leave him with me!"

Sans nods slowly, he's trying to make sense of the situation but it's somehow difficult to comprehend. He's going to be a big brother to a little skeleton child whose bones might snap the moment he lays his indelicate hands on it.

But he's always careful with everything, so it confuses him why he would think that.

"Will it snap in half if I touch it?" He asks.

Gaster lets out another small huff, and he notes how it sounds shakier than before. Is Gaster okay? Is he...laughing?

What's so funny?

"As long as you are careful with them, they'll be fine." Gaster says.

Sans blinks and nods again, eyelights going back to observe the child from the footage. He can be careful, he always is.

Unlike that person who forever doubted his ability to take care of a baby, Sans won't be so nervous. Anxiety only makes room for error.

---

The third time Sans remembers something different is when Gaster takes him to a trip around the underground for educational purposes.

The royal scientist was working on a major project called the CORE, that if successful, would soon replace the simple magic-run appliances that monsters have had for several centuries; and Gaster was visiting each section of the underground  to see which would be best to build the CORE in.

Often, human objects would fall from above ground. One of those things was a book detailing a power plant or engine or source of energy— Sans hadn't paid much attention to it, too occupied with looking at footage of the skeleton child, but Gaster had been struck with inspiration.

His sudden burst of determination (isn't that dangerous for monsters?) was apparently contagious, since his entire team had jumped onto the bandwagon.

It would change life for monsters as they knew it.

So Gaster brought Sans along. It was a rather quick trip, but to expected. The underground only had so many places to go to after all.

The names of the biomes were a little on the nose. Sans could finally understand why someone said that Asgore sucked at names.

Enjoying the sights and somewhat familiar temperatures of the underground, he realizes he's never gotten out this much, and he's never seen so many different monsters before. The only ones he really interacted with were from Gaster's team and even then he barely saw them, usually in his room, studying.

In the end, the CORE was set to be built in a place called Hotland. The heat could be used as another source of energy, but overheating could also be a problem.

Sans remembers one sector called Snowdin, and how a river going through the whole underground apparently connects all of the locations.

There's a niggling thought that's just waiting to be said. Maybe someone could send ice from Snowdin to the CORE through the river? That idea sounds...familiar, he can't put a finger on where he heard it before, but it sounds like a nice one.

He tugs on one of Gaster's pinky fingers, intent and curious about how it could work.

Now, if he had a brain, his head would probably be hurting from the amount of muttering and grumbling that Gaster's been doing. The older skeleton seemed like he thought it through and approved, from the way he'd been positively beaming. Gaster smiles a lot, but they're rarely genuine.

Sans is glad that one of his strange thoughts managed to be of help to his creator, but after he got pat on the head, it looked like Gaster suddenly thought of something else. He's been murmuring about things that Sans doesn't understand much of yet, but maybe soon.

If he studies a lot and becomes Gaster's official assistant, he won't feel stupid.

He's really smart though. Sans and Gaster and all of the monsters they've met know that, so where did that come from?

"Looking back on Sans' fight makes me feel like an idiot."

What fight? He's never fought someone before.

"He's such a nerd, just look at his dialogue and how Papyrus tells us that Sans is a giant sci-fi fanboy. What a goddamn nerd. I love him."

"He's clearly a fucking scientist."

"No! He's a nerd!"

"He can be a nerd AND a scientist then, geez!"

What's a nerd? They're calling him a nerd?

Unknown to him, Sans' eyelights go hazy, moving minutely as he stares off into space like he's seeing something else.

Gaster's already narrowed gaze narrows even further once he looks up from his mumbling tangent and notices his protegé's current state.

A nerd must be someone smart and knowledgeable, if they could be interchangeable or related with a scientist. One who likes science? Sans is sure that sci-fi means 'science-fiction' even if the word isn't something he's come across in a book or page before.

Sans likes science, he must be a nerd.

Jolting at the touch of a hard hand, Sans' eyelights shoot up towards his creator, one of his many hands laying on his small skull. He blinks curiously. Is there something wrong?

A familiar faint static enters his head.

"Sans, you've been rather absent-minded lately. Care to share?"

It's a request, but Sans takes it as an order like always.

"I'm a nerd." He says like he's sharing a giant revelation. One that makes Gaster rattle from the effort it takes not to bust a non-existent gut. The scientist heaves a quiet sigh, the breath coming out shaky from remaining laughter.

"I see. Let's go, we have things to do and plans to make," Before he turns away, Gaster glances at Sans in mild concern. "Perhaps it's time for another test as well, be sure to stay still this time, you might hurt yourself again."

Sans can barely hold in the instinctive terror that rises.

Swallowing down the confusing fear, the small skeleton nods firmly. Even if he's scared, he has to go through with it; better him than another poor monster.

Why did I think of that?

He ignores any and all thoughts that swirl in his mind, content in following behind his creator back to the laboratories, silent and accepting.