Archive of Our Own

When Sans finally had the rare pleasure of personally meeting the Dr. Wing Ding Gaster, he was not expecting this.

(Funny. No one was ever expecting this.)

The stout little skeleton was expecting what he had seen in the professors and teachers before him - a stoic, stern, strict, and reserved monster, much like the other scientists he had passed on his way here that littered the halls and stealthily scattered throughout the laboratory. The scientists that day busied themselves more than usual it seemed, almost as if to distract themselves from the newbie, Sans noted absentmindedly as they all hurriedly scrambled about the floor, dangerous chemicals in one monster’s shaky arms and vital computer data in another’s firm claws. They seemed like the professors and teachers before him; straightforward; objective driven; given one specific path and told to go. 

(Like rats , Gaster laughs, and he sets up all the traps much the same).

On the contrary, in stark contrast to the others working around him, the Royal Scientist was an open book - very kind and outspoken, with a warm welcoming demeanor and a fairly minimal enforcement of trivial lab rules regarding cellular devices and uptight dress code. It’s what allowed Sans to walk into work every day in a blue hoodie and with his cell phone still turned on. Like Sans, Gaster also found himself almost constantly smiling, which could have either been the formation of his face or the fact that he was so giddy most of the time.

And, unlike Sans, the doctor also tended to ramble. Minutes would evolve into hours chipped away from Sans’ already busy day (not that he minded at all; he was still getting paid for putting up with it in the end). Sans eventually came to learn that Gaster spoke with his hands much of the time, both using expressive and exaggerated gestures during his lectures as well fluent, swift sign language while interacting in the midst of very important work that he would rather not disturb with his chatter.

Needless to say, the short skeleton monster had a feeling that he was going to enjoy working here from day one.

(Needless to say, he was very, very wrong.)

There was another feeling, too; it wasn’t quite dread, and it wasn’t quite anticipation, either. It was somewhere in between, in the odd moments of strange looks from the professer and the uncomfortable silences that loamed the halls, like a very well kept secret. But Sans assumed it was his nerves getting the best of him and thought nothing of it.

The first few days were a bit tense, seeing that Sans had never been an assistant before, much less an assistant working alongside the most brilliant mind in the entire underground next to Dr. Alphys, but he managed. He actually performed quite well and was far more helpful then he ever thought he could be (but still, he couldn’t bring himself to look Gaster in the eye, he was always smiling at something-)

In the following weeks, however, he had eventually managed to establish a comfortable working routine and was no longer intimidated by Gaster’s height or status (or stare or smile or presence; but he still constantly felt like the punchline of a joke the doctor told the wind).

It only took a couple more months after that for the skeleton to grow comfortable enough to give Gaster the nickname “dings”. The first time he’d used it, Gaster’s face lit up in delight, and he found himself smiling a little wider that day.

(There it was, the trap was laid, and now to test the bait.)

Gaster started with the experiments shortly after that; not the operational experiments, not the ones that required Sans to surrender his soul for inspection or to strap himself to the table. No, not yet at least, those were for later, and they started very small. They pushed Sans’ trust to the limit, in by inch. They were Gasters own private, uncatalogued experiments.

Ones that the other workers noticed, but decided not to say anything about, because they knew his routine by now, and opted to stay out of the way (for their own safety).

Gaster often asked Sans to stay after to help him clean up the lab or complete left over paperwork. As expected, his assistant complied with no hesitation. Sans was willing to help and eager to please. The same outcome was achieved when asking him to come in early, albeit it was done groggily and for the most part unfocused. And again, when asked to run to the store or to complete errands otherwise not listed in his job description (personal or professional, it did not matter), the same outcome was reached: Sans eager to please, and happy to be of service.

These considerably small “tests” quickly became regular requests that eventually worked their way into Sans’ own personal routine - frequent actions he’d learned to comply to after a short while. Before getting to work, he would stop by the coffee shop and get him and his boss some much needed caffeine that Gaster always seemed to neglect to acquire himself, before coming into work early to finish the paperwork ‘unintentionally’ left upon Gaster’s departing the night prior. He often stayed after late into the night to help wrap up unfinished tests and diagnostics. Gaster fawned over him.

The other scientists kept their distance from the two.

When Gaster recommended the magical modifications and the installment of the Blasters, Sans immediately grew weary, mumbling something about his HP and ultimately declining the project. Damn, Gaster must have jumped the gun and overlooked his assistant’s eagerness to please. Despite the royal scientists guarantee that with weapons like these he wouldn’t even have to worry about losing 0.5 HP, Sans shook his head adamantly. He cracked some egg pun that Gaster didn’t catch in his angry and disappointed state. What a disappointment.

No matter. Gaster could play this game. Gaster could wait. He set the trap and he was going to see it through.

(He could wait, and he could pull his own strings, too.)

Shortly after the royal scientists’ offer had been shut down - oh, what a shame it was, Sans was the perfect build and the smartest assistant he’d ever had! - Gaster shared with Sans his own private project; something he sternly told Sans was a secret and  a great privilege to know of. A time machine capable of travelling back to before the humans trapped their species underground. A machine that could reverse their defeat and free the monsters.

“You’re the only one in the Core most qualified to assist me,” Gaster would tell Sans proudly, frequently. “You’re the only one privy to this knowledge, and this project would absolutely thrive with you working alongside me.”

Needless to say, Sans agreed in a heartbeat.

And for the most part, Sans was rather helpful.

Until the last request.

“you uh… you want me to what, dings?”

“You may not have ears, Sans, but I know you heard me clearly. I do not need to repeat myself.”

“... jeez, i don’t know how… i don’t think this is…”

“Sans, imagine a world where monsters are not quarantined beneath the earth, cowering at the feet of mangy humans! We can rewrite history! This machine is capable of carrying one monster through time, to before the war began. To before the humans plotted against us.”

“i-i mean, i get that, but this is kinda…” Sans wrung his hands together uncomfortably.

“…look, i get where you’re coming from, but this feels… this is wrong. there’s gotta be another way. you don’t know what this could do. and i-i’ve only got 1 hp, doc. how do you expect me to take out the entire human race when there’s a chance i won’t even get through the first village without dying? seems kinda reckless, g.”

“Yes, but modifying your blue magic with my prototypes will strengthen your-”

Sans abruptly cut him off, shaking his head in disbelief.

“are you hearing yourself?” he scoffed. “you want to turn me into a superweapon, send me back in time, and slaughter the human race. y’know, i heard that you had a screw or two loose, but i just figured that… they didn’t understand you.”

The stout skeleton sighed and turned around. Gaster held his breath and clenched his fists, allowing the other to speak.

“i get that you want to save the monsters stuck down here and all, but where’s your morality?”

What a foul, foolish word.

“i like working here. i like working with you, dings, but i can’t just pretend that this is okay. i won’t be working on this project with you anymore. if you won’t find another way out of the underground, i’ll just have to do it by myself - without wiping out an entire race.”

And with that, Sans left.

And Gaster seethed.

He sent an email to his colleagues and coworkers shortly after:

”Private development workshop tomorrow. Facility to remain vacant. Faculty dismissed, doors will be locked.”

Then he removed Sans’ name from the send list.

-

Sans arrived on time - not early, and with only one cup of coffee. When Gaster flipped the debilitating device was on, the coffee spilled to the floor and Sans crumbled to the ground like a marionette without its strings.

And Gaster couldn’t help but laugh.

-

“i bet you get off to this kinda thing, don’t ya doc?” Sans spat bitterly, sighing as he

visibly relaxed against his restraints after his attempts proved useless.

“kidnapping and torturing your assistants when they don’t comply to your every command like pets at your feet? now that i think about it, it does sound like something you would do.”

Gaster rolled his eyes as he forcibly led his assistant to the lower part of the Core, to Gaster’s own personal laboratories.

“Do you ever stop talking? You’re quite annoying. Perhaps I should have gagged you as well.”

“you’re a bit of a freak, aren’t ya?” Sans retorted, before he gathered a large amount of blue saliva in his mouth and spat it up into his captor’s face. The magic liquid rolled down the older skeleton’s cheek almost imitating a tear. Gaster didn’t so much as flinch.

Instead, he drew his head back and chortled loudly, before aggressively pushing Sans to the floor and stomping on his chest.

“Oh, I’m the freak? Compared to you, a monster who frequents shifty red light establishments on a daily basis? Sleeping with as many paying customers as possible before their baby brother gets home? Scraping together as much money as you can after work to pay for the necessities that a measly lab assistant’s wage couldn’t possibly afford? Coming up with pathetic excuses and petty reasons as to why you can’t spend time with your only family, when in reality it’s because you’ve been occupied whoring yourself out to half the underground? As much as I’d like to agree with you, I am afraid that you’re the freak here, Sans.”

The lights disappeared from Sans eyes as the blue flush drained from his bones.

“... y-you’re fucking sick.” He wheezed.

“On the contrary,” Gaster lifted his foot and continued dragging the small monster through the maze-like halls. “I fail to see how this knowledge makes me ill in the least. Quite the opposite, in fact.”

“really? you don’t see how stalking me and watching me without my knowledge is an issue? as if this fucking scenario wasn’t problematic enough?”

“But of course. My assistant is one of my most valuable assets here in the lab, I cannot afford to have something bad happen to-”

“then what the fuck is this, doc!?” Sans hollered angrily, holding up his magically restrained limbs and violently swinging his tied arms at Gaster.

The taller monster swiftly took both of Sans’ thin wrists before they could land a blow on him and effortlessly plucked him up from the ground before continuing to walk calmly.

“Simply a regulatory precaution. Something all of my assistants have had in common from time to time. They find that morality and goodwill keep them from accomplishing basic objectives, impacting their usefulness in the lab, ultimately hindering their progress. Thus, hindering my progress. And I don’t have much patience, so consider this a… friendly reinforcement- a reminder, rather, that we are here to free monster-kind from the underground, not bicker over unimportant matters-”

“are you actually hearing yourself doc? unimportant matters? so i’m an unimportant matter to you?”

Gaster sighed, deeply annoyed by the fact that the monster was still trying to uphold a conversation with him.

“Don’t be foolish; only your opinions on the matter are unimportant. I require you to be absolutely compacant-”

“and all those other monsters down there, your neighbors, your coworkers - their safety and well-being are all unimportant matters?” Sans beckoned, his voice losing all of its venomous undertones and devolving into a heartfelt plea for morality.

“Do you see what I mean now when I said morality is a hindrance?” The royal scientist scoffed, coming to a stop at a large door and vigorously punching buttons in (careful to ensure Sans didn’t see them).

“Just listen to yourself, Sans. I could go on and on about how this might seem morally

wrong, but it’s simply illogical.”

The door mechanically inched open, revealing a medical table, several machines, and a tray of needles and instruments akin to torture devices.

“jesus christ, i can’t fucking believe this is happening.” Sans squirmed violently, not phasing Gaster’s grip at all.

“That makes the two of us. Honestly, you’re questioning the most intelligent monster in the underground. I thought you would be brighter than to question my-”

“brighter? hah! alright, first of all-”

“I’ve heard this all before, Sans.” Gaster groaned, tossing Sans carelessly onto the table.

“ow! shut up! shut up and fucking listen to me for once in your goddamn life, gaster!”

For a brief moment, Gaster was taken aback, and allowed Sans to sit up on the table and look him in the eye.

Gaster couldn’t remember if Sans had ever looked him in the eye.

“ i can guarantee you personally, as the scientist who stood by your side for the entirety of this project, that everything you’re planning to do right now is not going to work! if this is how you’re planning on saving the underground, you’re gonna have to explain to King Asgore why it is you failed.”

Gaster found himself taken aback again. Not out of surprise, but out of rage. How dare this little runt question his abilities? And after he had offered him the opportunity of a lifetime, too?

“I do suppose you’re right sans. If things do not pan out, it will be me who will have to report to Asgore why it failed. After all,”

Gaster caressed the side of Sans’ skull gently, before pulling it back and slamming it back down against the solid table. The small skeleton immediately stilled.

“If this experiment fails, it means you did not survive it.”

And then he went through the steps in his head.

One: Ensure subject is restrained and equipment is on and attached respectfully.

“... hnngh… wh- gaster? doc, wait- dings, don’t do this. please don’t do this, i-i don’t want this.”

Two: Fill blaster capsule with magic and place capsule into the sanitized needle gun, careful not to shift contents or misfire prematurely.

“But of course you do, Sans. It will improve you. Don’t you want to protect your little brother?”

Three: Summon the subjects soul or other magical container that has the capacity of absorbing capsule.

“i don’t want this- i-i’ll tell everyone what you did- what you do down here-”

Side Note: Euthanize subject if magic backfires to avoid magic combustion. Anesthetic unnecessary.

“Oh don’t be foolish. They already know. And the king cannot be bothered with petty matters like a skeleton’s crazy, outlandish fever dream. Who knows, perhaps you won’t remember most of it? Wouldn’t that be merciful? I wish I had that liberty. Goodnight, Sans.”

Final step: Insert needle into capacity-

“AAAAAAAAAAHHHHHH!”

-and inject the capsule.

Sans’ fearless facade had all but disappeared, lost to a mess of tears and screams that echoed throughout the hallways of the laboratory. Thick blue magic oozed from the insert point of the gargantuan needle, the burning sensation spreading through the base of his spine and the inside of his buzzing skull.

“Do not worry. This is only going to hurt for a short while.”

The now unconscious skeleton convulsed on the table as magic frothed at the corners of his mouth and lolled down the sides of his cheeks. The capsule dissolved within his soul.

And now, summon the blasters, retrieve the bone drill, insert the transition tube through the left eye and begin the surgical operation.

-

When Sans finally had the rare pleasure of personally meeting Dr. Wing Ding Gaster, he could have sworn that he had met him before.

(Funny. A lot of people said that about the doctor.)

Wing Ding Gaster had written to him weeks after his release from the hospital (the cause was unknown, but he was there for a while apparently; it was believed to be a magic overload of sorts that ultimately erased part of his memory) - and claimed to know how to prevent further overloads and hospital visits.

“You’re almost too powerful of a monster,” Gaster said to him the first (?) time they formally met. “Not quite a boss monster, but certainly the capacity to be mistaken for one. And a skeleton monster, at that. How interesting…”

The doctor had an obscene fascination with the holes in his hands.

“i don’t know how i got them,” Sans admitted, “but they hurt all the time. same with my eye. hospital said i had too much magic, i guess? if that makes sense.”

Gaster nodded understandingly. He had a coy smile that unsettled Sans to the core.

“Yes, that makes perfect sense. Especially with such low HP-” (when did Sans tell him that?) “-it’s amazing that there were such mild effects! However, from skeleton to skeleton, I have a proposition for you.”

And so, although Gaster did notice the hesitation, the brief presence of distant nostalgia, Sans accepted the proposal. He agreed to submit to the training for the new magic, and its blasters, accordingly. And he performed quite swimmingly, quickly learning how to summon and initiate his newfound abilities. And no matter what Gaster asked of him, Sans was always just so ready to satisfy, so eager to make him proud.

After some time, Gaster invited Sans to work alongside him as an assistant of the Core. The wage was higher this time around, though (perhaps Gaster felt bad, or perhaps he wanted to ensure the other skeleton would agree). Needless to say, Sans did agree.

His colleagues gave him shocked looks and kept their distance. Some spoke to him as if they knew him, seeing an old friend after a long while apart.

Only he had no idea who they were.