Plague Underground Chapter 3: PART THREE, an undertale fanfic

PART THREE

CHAPTER EIGHTEEN:

"Oh n-no…What i-is this t-thing?"

Alphys stared in horror at the slowly moving organisms which were crawling en masse throughout Toriel's dust underneath the microscope. They looked like tiny pills with even tinier tendrils and were multiplying at an alarming rate, though that, to be honest, was an understatement. The dust was absolutely swarmed with these unidentified bacteria. There was so much of it that Toriel's once shining dust was now a slightly milky off-white, though that color change was admittedly difficult to see without a microscope.

She conducted further research, and with each new thing she discovered, the more terrified she became. This thing, whatever it was, it seemed to be unstoppable.

She remembered: Sans had taken a small handful of her dust as a memento for her memory, but she doubted herself as usual and called to confirm it first. She dialed his number as quickly as she could.

She called. No answer. She tried again.

She called. Still no answer. She tried again.

The third time she called, Sans finally picked up.

"Heya," he said, sleepily, "What's up?" It was almost 5:00 AM.

"Sans!" Alphys said, fear growing in her voice, "D-did you p-pick up any of Toriel's dust?"

Sans didn't want to answer because that memory brought back a lot of highly traumatic pain, but he sensed that the question was extremely important.

"Yeah…I've had it for a while. There's still a little bit in my hoodie."

"BURN IT. B-BURN IT AND EVERYTHING IT T-TOUCHED."

"I-I don't know what it is about monster dust that makes it grow so q-quickly, but this thing: this is how Toriel died," Alphys said, pointing to the unidentified bacteria in a petri dish, "And if my predictions are c-correct, it's how Frisk died t-too."

Sans stared at it with wide eyes. Frisk. He brought that with him. And it killed the person he loved the most. Second to Papyrus, of course.

"I never shoulda made that promise," Sans seethed, rage slowly growing. He felt guilty for that feeling; he knew Frisk could never have known what he did, but the fury built up inside of him anyway.

Sans had just recently celebrated his ninety-day sobriety mark, but this realization, it made him want to drink himself into oblivion and never wake up. He snapped himself out of that dark desire by clenching his fists as hard as he could.

"How long does this stay dormant? How quickly does it spread?"

"F-From my r-research," Alphys said, pointing at various charts and figures of the tests she had done, "These bacteria multiply very f-fast in monster bodies, but for some reason, this disease doesn't have any s-symptoms u-until it's too late to t-treat, at least from the samples of Toriel's d-dust."

Sans looked at her, confused.

"So, the sniffling and sneezing…that meant she was already doomed? Why did it take so long for her to, ya know…turn to dust?"

"It lies d-dormant for at least s-six weeks, and sometimes several months, based on Toriel's samples. From my t-tests on smaller monster c-creatures, some symptoms are gradual and s-some come on r-rapidly. And the mortality rate…i-it's one hundred p-p-percent for our kind. These organisms d-don't usually last l-long on surfaces for more than t-three to f-five days normally, but since they seem to cling to our dust and the p-particles of it left behind when we t-touch things, I've found that it has been able to survive t-three to five w-weeks."

"And from what I know so f-far," Alphys said, pointing to another petri dish, also swarming with bacteria, "It's extremely c-contagious."

Sans slowly backed away.

"I went to the bar almost every day. I always put my hands in my pockets."

Sans had a horrible epiphany. He cowered on the ground in a fetal position.

"I've…I've killed everyone…"

CHAPTER NINETEEN:

Outside of his house, Sans filled up a large metal barrel full of all of his clothes and possessions; he desperately wanted to keep his hoodie with Toriel's dust, but he believed everything Alphys had said and what he saw himself. He was wearing the only clothes he had left, which were green scrubs that he got from Alphys's lab. His crosswords, telescope, science and joke books, trombone, and all the other various things he collected in his life were thrown into the barrel, which he poured gasoline on top of. He lit a match and threw it in. Everything quickly burned except for the telescope and trombone.

Papyrus saw the smoke from his sentry station. Concerned, he ran over to where it was coming from. He looked at Sans in front of the burning barrel, horrified.

"Oh my GOD, Sans! What are you doing?!"

"The right thing," Sans said, rubbing his temples.

"What's in the fire?! Why are you burning everything?!" Papyrus looked at Sans, suspicious.

"For the love of god, Sans! Were you drinking again?!"

"No. I'll never do that. Ever," Sans said, looking Papyrus straight in the eyes. Papyrus looked at him, relieved; he knew he wasn't lying this time.

"Papyrus, get your things. You need to throw them in there too," Sans said as he entered the house, going up to Papyrus's room.

"What? Why?! What on god's earth is going on?!"

"We're all in horrible danger, Papyrus," Sans said, running up the stairs with Papyrus close behind him, "Alphys explained everything."

"Sans, what did she say?! Why are we in danger?!"

Sans yanked Papyrus's cape down to his level.

"Remember Frisk? That kid brought somethin' with him! The sickness that killed him also killed Toriel. If that disease is as contagious and deadly as Alphys says it is," Sans said, lowering his voice, eyes turning black, "We're all gonna die if we don't do somethin' immediately."

Sans thrust Papyrus an extra pair of blue scrubs in his size into his arms.

"Take off your battle body. Everything could be contaminated."

"What do you mean, 'everything'?!"

"That means everything, Papyrus."

Papyrus wanted to protest, but Sans was deathly serious. He went into the bathroom and changed his clothes, for the last time.

"Your gloves," Sans said, pointing to them, "Take them off."

Arms trembling, Papyrus slowly took off his gloves.

Sans took Papyrus's entire battle body and threw it into the fire. The barrel fell over, and soon their entire house was up in flames.

"Oh my god, Sans! Call the—"

"No. Let it burn."

Sans and Papyrus stood together in silence as they watched their house crumble into ashes. Everything they knew and loved burned right in front of their eyes. Sans was clinging onto the faint hope that this could prevent further spread from his exposure, but the more he thought about it, the more he realized that it was simply denial of the horrific events that were inevitably going to happen.

He wanted a drink. He NEEDED a drink. But he couldn't, and wouldn't, have any more. Sans clenched his fists in the pockets of his scrubs.

CHAPTER TWENTY:

It had been a few months since those wacky skeleton brothers burned down their house at Sans's insistence. Some thought that it was an insurance scam while others thought that he was drunk again; he had built quite the negative reputation for himself while he was drinking.

And it was quite weird for the townspeople to see Sans and Papyrus refusing to have their home rebuilt and living back into the proper town of Snowdin. Sans rambled to the others about an inevitable apocalyptic plague: was he still an alcoholic? They couldn't be sure based on his insane conspiracy theories, but he didn't move, act, or speak like a drunkard anymore.

Sans and Papyrus still had their cellphones, which they had kept in the pockets of their scrubs when they changed their clothes. They lived in tents at their work stations, which Papyrus initially didn't like, but strangely warmed up to the idea as it felt like camping. Sans demanded that they each have bags full of hand sanitizer to constantly wash their hands. They physically stayed apart from each other for most of the day, but often talked to each other on the phone.

Sans would order takeout from Grillby's and have the bag delivered to his tent. It wasn't hard to locate because it was almost covered from top to bottom with a shield of bones. The tent was camping grade with a foliage camouflage tarp which could also be easily picked out in the snowy white grounds of Snowdin.

Grillby walked over to the tent, carrying Sans's takeout bag. He placed it by the one unarmed portion of the tent. He stared at it, confused.

"Sans, is all of this really necessary? Why won't you and your brother come back?"

Sans slightly opened the tent and reached out for the bag with his arm, pulling it in, and closed the tent again.

"Hasn't Alphys told anyone about this disease yet? Cuz, ya know, I saw it for myself." Sans said, peeking out at Grillby through the one "window" of the tent.

"I only know a little bit, but I don't think anything like what you've been talking about will happen," Grillby replied, well aware of the insane rumors Sans was trying to spread around Snowdin.

Sans opened the bag and began eating the cheese fries and double cheeseburger he ordered. Despite the long way it took for Grillby to get to his tent, the food was surprisingly still warm.

"Grillby," Sans said, between bites, "You need to shut down your bar, make it delivery only or somethin'. I did a lotta dumb crap when I was drunk, but you gotta listen to me 'bout this. We had to burn down our house. I exposed everyone to whatever this weird sickness is, and we can't afford to go back and do it again."

"I don't think I should go that far. Besides, that bar is like my second home. I could never see myself closing it down for something that probably won't happen."

"It's going to happen," Sans said, eyes turning black in an intense stare, "If we don't do anything right now to stop it, you, me, everyone in Snowdin will die. Possibly the whole Underground too."

"I think you're overthinking quite a bit," Grillby said, slowly backing away from the tent.

"Hasn't Alphys told ANYONE about how serious this is?! If you hear anything from her about this, you'd better believe every word she says. She did the dust analysis. She saw what was in it. I know why you won't believe me given all the things I did, but for the love of god, you need to listen to Alphys!"

"Sans, Alphys only talked about something that involved coughing. For all we know, it could just be a cold, or the flu, or allergies. How do you know that something like that will wipe us all out?"

Sans turned away from the window and began to fidget with his hoodie strings. He stopped eating his food, and sighed.

"Thanks again for the burger."

A week later:

"Masks? We have to wear masks now? Just for a cold? Nobody has ever died from having a cold," one disgruntled local grumbled as he saw the new mandates on the door to Grillby's bar.

"Sorry sir, no mask, no service. I'm not taking in more than fifteen people in the bar anymore either," Grillby replied, facing the door. He was wearing a fireproof mask.

"Oh, go to hell with that bullshit! Since when has there ever been a pandemic?! Never, that's what!" The customer clenched his fists, tapping his feet on the ground, annoyed.

"Look, I don't want to do this either, but believe me, I've now heard some more about this illness and how quickly it spreads. The least we can do is put on protective gear and hope this doesn't get worse." Grillby then called to a waiter behind him to serve some customers drinks and food, which the man outside the door didn't quite hear.

"Oh yeah? Says who?!"

"Sans seems to be very aware of this situation, and he gave me direct information from Alphys the other day. From the looks of things, it could get serious if we don't do our part to stop the spread."

The customer gawked at Grillby.

"Buddy, if you're taking advice from a rambling wino, you've got way more problems than this ridiculous 'disease'."

"Trust me, I couldn't believe it either," Grillby stopped for a moment to polish the window, "But this is not just what Sans is saying. This is all information relayed to us by her as well. She was the one who created this mandate, not me. But according to her, and her only, we may get through this if we follow these simple rules."

The customer stared down Grillby, his expression getting more and more intense the longer he was looking at him.

"Now, are you letting me in or not?"

"No shoes, no shirt, no mask, no service. Besides, the bar is at full capacity, you can call this number if you want takeout," Grillby said, showing him a phone number posted on one of the windows.

"I'm not calling no goddamn number! I want to be let in right now!"

"You'll have to get a mask first, and wait," Grillby said, going back to the bar to serve the people who were already there.

Protests and counter protests started to form about the new mandates which most people couldn't stand. Sans looked on at the few people who would come by his tent with their stupid little signs and roll his eyes at how ridiculous they were acting. Well, not that he had any room to speak on "acting ridiculous," he was already well known for doing just that at Grillby's bar.

Out of boredom, Sans would sometimes come out of his tent to sit in the cold air, enjoying the beautiful, snowy days. He felt tempted to go by the door to the Ruins again, but every time he thought about it, he would succumb to the dark and intrusive thoughts replaying the day she died, over and over. He just decided to stay where he was and threw snowballs at nothing; it was a good excuse to do something with his hands and to get his mind off of alcohol for a while.

"Sans, do you have any more news to report?" Papyrus asked, calling him.

"Nope, nothin'," Sans replied, clenching and unclenching one of his fists.

"I guess, there won't be any more humans to look out for," Papyrus said, deep in thought.

"Heh, you're probably right. So much for doin' a job, huh?"

"Sans, do you think, we're going to by okay? I mean, I'm great and all, of course, but I'm just not…great enough to fix this situation."

"I dunno, to be honest. This ain't the best time of our lives for sure."

"That is most arguably true. But fear not! I, the Great Papyrus, will make this transition as smooth as possible…if possible."

Sans sat awkwardly in silence for a moment.

"Hey, uh, Paps?"

"Yes?"

"Do I… make you proud anymore?"

"Of course, Sans! Why would you ask that?"

"I've just, I've just done too much to you, ya know?" Sans took a heavy breath.

"Asgore, he…saved my life. I can't thank you enough for making him come over. But…" Sans sharply inhaled, "Did I…deserve it?"

Papyrus paused, trying to think of what to say.

"If you didn't have someone as amazing as me to care about you, you would have died. Nobody deserves that, especially not you, or, well, me." Papyrus picked at his scrubs.

"And you know what else, Sans? The fact that you chose to change is what makes me proud of you. If you stayed the same as you were back then, then I wouldn't be. But you're not. And even though you did things that hurt me, you're still my brother, and I am your better brother. I'm too great of a person to hold that kind of grudge against you when you've clearly made the effort to be better. So, worry not! I, the Great Papyrus, have forgiven you long ago!"

"That means a lot to me that you have. I was a piece of crap."

"But you were MY piece of crap! NYEHEHEHEH!"

"Heheh, guess you're right—"

Sans heard someone coughing, faintly, in the distance. They were having a coughing fit.

Sans zipped up his tent and put a bone fortress around it, guarding himself.

"Papyrus, whatever you do, stay in your tent and DO NOT come out for anything! Put a wall up! Don't let anyone near you, me included!"

"What?! What's wrong?!"

"I—I heard someone. They were coughing!"

"Um…" Papyrus fell silent on the phone a little bit, confused. "Isn't that, normal?"

"Dammit, Papyrus! Don't you remember what happened to them? First it was Frisk, then Toriel, and now it's someone else! It—it's spreading!"

"Sans, people cough all the time. How do you know it's not just allergies?"

"Yeah, uh, I thought that too at first with Toriel," Sans said, trying to peek out of the only "window" of the tent, "But we can't leave our tents, not now, not ever!"

"That's…a massive overreaction," Papyrus said, tapping his fingers on the floor.

Something blew in the wind. It looked like snow. But it was too fine, too shimmery, and too powdery to possibly be snow. Sans saw it blowing outside of his tent, and when the wind carried it over to his station, so did Papyrus.

"Is that…what I think it is?" Papyrus asked, trying to hide his growing fear.

More of it kept blowing around, some of it right by their tents.

"We. Are. Fucked," Sans said, not hiding his.

Alphys and Undyne were holed up in the lab. She finally told Undyne the truth about the nature of this devastating illness, and when she heard how bad it really was, Undyne stood up, spear in hand, ready to burn things to the ground when necessary.

"Humans, monsters, it doesn't matter if we get their souls anymore," Undyne said, polishing her spear, "We have to kill all humans, no matter what. They brought this upon us, and we can't let them do it again."

"I-I think the biggest concern right now is figuring out how to neutralize the p-present t-threat," Alphys said, searching on her computer to find anything that could possibly help. She found nothing useful.

"I…I don't t-think, we're going to m-make it out of this," Alphys said after an awkward silence.

"Well, we can't just give up! Everyone's hopes, everyone's dreams, we can't let them be destroyed just because we didn't try!"

Alphys got off from her desk chair, away from her computer. She was finally ready to tell Undyne the truth. Or, rather, show it.

"That's not quite my p-point I'm trying to m-make," she said, wiping her eyes. "You need to f-follow me. Downstairs. I can't l-live with m-myself if I don't show you what I've done. I'm t-tired of hiding."

"Wait, there's a basement in your lab?"

Alphys slowly nodded. She reached out her hand to Undyne, which she took, following her to the elevator which led to the true lab.

The elevator landed with a thud. It didn't crash, but it had been in disarray for many years from neglect. The door opened.

This area of the lab wasn't well-lit. Flashing fluorescent lights hung above the ceiling, giving it an eerie vibe. The walls were made of blue steel plates, giving it an almost prison-like feeling, but more depressing.

"What…is this?" Undyne asked, trying to get a full view of the place.

"This is the r-real area where I do m-my research. This is where I made the i-ingredients for Frisk's t-tonics, but m-most importantly," she said, leading Undyne to a closed door, which she was about to open, "T-this is what I-I've done." Alphys opened the door.

A large white blob with multiple, melting eyeballs and a gaping mouth full of jagged teeth came slithering towards them. Undyne formed a spear and threw it at the thing coming at her. The spear phased right through it. She started to form a wall of spears until Alphys tugged at her arm.

"U-Undyne, please stop! I-It won't h-hurt you!"

"What do you mean it won't hurt me?! What the hell is that?!"

Alphys gulped.

"…M-my experiment…"

The large white blob with the melting eyes rubbed itself against Alphys affectionately, which she petted back.

"T-There are…more around h-here somewhere. They—they l-like to h-hide."

"'They'? Alphys, what are they?"

Alphys led Undyne to another computer, this one much bigger than the one upstairs. On the screen was details about an odd experiment involving injections into dying monsters.

"These, t-these were once p-p-people."

Alphys took a deep breath.

"Undyne, A-Asgore tasked me with f-finding a way to b-break the barrier with m-monster souls. Because our s-souls don't last p-past death, I had to find a w-way to make them…s-stronger. You…y-you know how humans have d-determination, right?"

Undyne nodded, still confused.

"These monsters…t-these monsters were about to f-fall down. I-I figured out a w-way to form a c-concentrate of d-determination. I, injected them w-with it. A-And now, t-they are these."

Undyne looked at her, still confused about something.

"But, how did they turn into, well, that?"

"M-Monsters do not have as much p-physical matter as a h-human body does. T-The determination w-was too powerful, s-so, they melted. T-They have no memories o-of who they once w-were." Alphys hung her head in shame.

"I-I've tried m-many times to return them home to their f-families, but I-I could never bring myself to d-d-do it. And now, w-with this plague that's a-about to k-kill us, it's t-too late. They may not d-die from the disease, b-but they can s-still get exposed, s-spreading it further. I-I had to t-tell you this, b-before w-we…might d-die." Alphys sat on the floor, head down and arms crossed over her stomach.

Undyne came down to her level, petting her head.

"Thank you. Thank you for telling me the truth." Then Undyne stood up and shook her.

"But we're NOT going to die! We are going to find a way to fix this, you hear me?! The whole world is depending on us! I know we can do it!"

"W-We…?"

"Yes, 'we'! I'm going to help you with your research, whether you like it or not! NGHAA!" Undyne formed a spear and broke it in half over her left leg. She then carried Alphys to the elevator and plopped her down. They went back to the first level.

"Now where do we get started?!"

CHAPTER TWENTY-ONE:

"Come on, there has to be something that kills this shit!" Undyne yelled, frustration growing, kicking an extra desk chair and toppling it over.

"I-I'm still trying to figure out what to do n-next," Alphys said, getting more and more anxious.

"Well, figure it out faster! We can't waste any time!"

Alphys remained glued to her computer screen, trying to figure out any ways this foreign disease could be cured. She didn't find any helpful results. However, she had photographs of the bacteria taken with her light microscope and did a reverse image search on the Undernet to figure out what exactly this disease was. She finally came up with a result: Pertussis.

"I need to conduct further tests t-to figure out h-how this can be c-cured. M-Monster bodies seem to be completely c-consumed by this i-infection. I d-don't know why that i-is."

"Don't we have anything to test on? What about those weird creatures in your basement? Maybe we can use them for something!"

"T-those wouldn't be s-suitable for these kinds of tests," Alphys replied, not turning away from the screen, "B-but, I do have some other test subjects that I have been using."

Alphys got off of her chair and led Undyne down to the True Lab, where, in the basement, were cages of monster rats and mice she had gathered for this exact purpose.

"Now, we just need to get started."

Testing, Week 1: