Chapter Text
Sans was in his lab, making the final adjustments to a very special project he was working on. A serum to turn you into the best possible version of yourself. A serum which, if it worked as intended, would make Sans' life, and the lives of his loved ones, better as a whole.
"Hmm... Almost there. Just a few more ingredients, and it should be ready." Sans carefully measured out the final dosage of his concoction, a mix of various extraterrestrial elements he'd collected over the years. And after everything, the tests, the failures, and after every time he almost succeeded, he did it.
Picking up the glass vial from the lab table, Sans begins to take a good look at his creation. "This is it." He thought. "This is the result of all my hard work... Rigorous testing and patience, all leading up to this. A potion to turn someone into something better than what they are, to relieve them of all flaws and hardships." ...He seemed nervous.
Sans took a deep breath and prepared himself for whatever was about to happen. He'd never tested this potion on himself before, but he was determined to make it work. He swallowed part of the mixture and waited for something, anything to happen.
...Nothing. He wrote down his observations, trying not to get discouraged. "November 4th. 200X. 1:01 AM. I have taken 10 centiliters of formula S8. Nothing so far. Only a tingling, salty taste. No noticeable chang-" His hand suddenly jolted with pain, leaving a rip in the paper. He felt a strange sensation wash over him. Both a euphoric and painful sensation. Then, Sans noticed his nails slowly turning cold and black, and he began to panic. Was this his imagination? A dream? A hallucination? Who knew? All he knew was that something big was happening.
He felt himself changing, as if his very being was being twisted and warped. He started to shake uncontrollably, his teeth chattering as they twist and contort in different directions. He collapses onto the floor, writhing in agony as he feels himself changing. He feels a dark presence inside him, a presence that's growing stronger by the second. It's like he's losing control of his own body. Sans feels his mind splitting in half, like a fractured mirror. One side of him screams in agony, while the other revels in the chaos and pain. He couldn't take it anymore. He passes out, falling unconscious on the cold, hard laboratory floor as the transformation inside him continues. His body unconsciously twitches and writhes in pain.
Eventually, Sans wakes up, taking in a large gasp of air. As he looks around, still taking in deep breaths of air as the last bits of pain subside, he finds that he can see things in a way he never could before. Colours are brighter, and the atmosphere is more beautiful. It's strange, but also fascinating. He gets up and looks at himself in the mirror, his reflection showing a different person altogether. He gasps and steps back in shock, not recognizing the monster staring back at him. He tries to speak, but all that comes out is a dry, cracked voice - not his own. He smirks at his reflection in the mirror, taking in his new ghastly appearance, as if he's getting some sort of sick pleasure from it. His twisted sense of pride swells as he involuntarily smiles at his new shape. He flexes his clawed hands, feeling the power coursing through his veins. He walks over to Sans' notebook, his eyes scanning the pages. He chuckles darkly as he reads through the entries, finding them amusing and slightly pathetic at the same time. He flips through the pages, skimming over years of notes and experiments. Deciding to add his own mark to the book, he picks up a quill pen and dips it into a small pot of ink. He writes on the ripped page, his scrawling handwriting contrasting sharply with Sans' neat handwriting.
"1:32 AM. All is well."
Restless and eager to explore his newfound power, he decides to venture out into the world. He takes off Sans' lab coat, puts on a pair of old boots and leaves through the front door of the lab. The hot air hits him like a ton of bricks, causing him to cough violently as he struggles to breathe with his new, non-existent lungs. But even in this unfamiliar environment, he feels a sense of exhilaration coursing through his veins. He wanders around the streets of Hotland, taking in the sights and sounds. He marvels at the chaos and disorder that surrounds him, feeling oddly at home in his twisted perception of the world. As he walks, he wonders if he can still teleport, and he decides to test it out. He closes his eyes and snaps his fingers, trying to will himself to disappear and reappear elsewhere.
Success! He disappears in a flash of light, reappearing outside the MTT Resort. He grins, feeling powerful and unstoppable. He prepares to teleport back, but his eye catches sight of a little shop on the side of the resort before he can. It looks like they have clothes.
Entering the shop, the nameless figure takes in the various different items for sale. His eyes land on a fluffy coat and a top hat hanging from a coat hanger, and he grins wickedly. He approaches the counter, looking over at the two teenage shopkeepers.
"Hi there, cutie! Welcome to our little shop. I'm Catty, and this is my best friend, Bratty!" One of them said. Catty was a short purple cat monster with yellow eyes and black and blue hair. Her friend Bratty was a tall, green alligator monster with blonde hair.
Bratty smiled at the newcomer, her eyes sparkling with curiosity. "So, what's your name, cutie? We don't see a lot of new faces around here." "Yeah, like, we know everyone."
The skeleton pauses for just a moment, as if trying to think of something to say. Oh right, I still don't have a name yet. He thought. Suddenly, as if he was a mother naming her child, he thinks of the perfect name. He smiles, revealing a mouth full of jagged, yellowed teeth. "Call me Latch." He says darkly. He reaches out to grab the coat and hat off the rack. "I think I'll take these." He pulls out a handful of coins, counting them out slowly. "100 G right?"
Bratty's eyes widened as she counted the coins. "Wow, Latch! You're so generous!" She grinned, reaching out to take the coins from him. "Yeah, that's 100 G. Thanks..." Said Catty.
Bratty squealed excitedly, clapping her hands together. "Catty! We're gonna be rich!" She grabbed Catty's hand, pulling her close.
Latch chuckles darkly, slipping on the coat and hat. "I'm sure you will be." He turns to face the two monsters, his eyes glinting with a hint of menace. "And tell your friends they can call me Latch now. That's the name I'll answer to from now on."
As Latch leaves, Catty gently pushes Bratty away. "Oh my god, Bratty," she says, her voice barely above a whisper. "Do you think he's okay? He seemed kinda off, you know?"
Bratty shrugs nonchalantly, twirling a strand of her blonde hair around her finger. "Eh, maybe he's had a bad day or something." She grins at Catty. "Besides, we got money! We should celebrate! Let's go to Snowdin later for some nice cream!"
As Latch makes his way into the resort, his mind wanders back to the lab, remembering the look of fear on Sans' face as he was transforming into Latch. It's a satisfying thought, one that he intends to savor for a long time. He makes his way through the lobby, his new outfit drawing attention from the other monsters staying at the resort. He smirks, enjoying the looks of shock and awe on their faces.
He decides to start with the most obvious target: the fountain in the middle of the resort. With a sinister grin, he walks over and kicks it, sending water flying everywhere. Guests scatter, squealing in surprise and annoyance. As patrons panic and employees try their best to clean up the water spraying everyone, Latch chuckles darkly, taking in the chaos he's created. He feels a surge of power course through him, his heart racing with excitement. This is what he was meant to do.
He spots a young human trying to run out of the resort but stops short when someone grabs a hold of his arm in an attempt to punish him for causing such a mess. With a cold glare, Latch pulls away from the grip, his eyes burning with anger. "You'll never catch me!" he snaps his fingers, disappearing in a flash of light.
Suddenly, Latch reappears in Waterfall. Dammit, should thought of somethin' cooler to say. He thought "I'll be back"? No, that sounds dumb. Should I have sworn? Yeah, I- Suddenly, a familiar face catches Latch's eye, making him lose his train of thought. It's Papyrus, Sans's younger brother. He's looking at Latch from afar in a state of surprise and confusion. Latch smirks, stepping closer to the skeletal monster. Latch towered the 10 year old, even with his short stature. "What 'cha looking at, kid?"
Papyrus looks up at the towering figure of Latch, his eyes wide with fear and confusion. "I... I thought me and my brother were the only skeletons in the underground," he stammers, taking a step back. "Who are you?"
Latch chuckles darkly, his voice echoing through the cave. "Oh, I'm just a friend of your brother's. Call me Latch. Now, why don't you run along and tell him I said hello?" He grins menacingly, taking a step away from Papyrus, clearing the way.
Papyrus, still confused and scared, slowly walks away from Latch. As the two walk in opposite directions, Papyrus' mind races with thoughts about the strange figure he just encountered. He stops and stands there for a moment, trying to think about what to do. He makes up his mind, deciding to go and tell Sans about Latch. Maybe if they work together, they can figure out what's going on. As he makes his way back to his brothers lab, he can't help but wonder why Sans never told him about Latch, and what kind of trouble he might get into if they don't figure out what's up with him soon.
Papyrus made it to the lab, making sure to thank the river person he got a ride from when he left, but as he entered, Sans didn't seem to be there. Papyrus wondered where he could be. As he looked around the lab, he noticed Sans' notebook was left open on a ripped page. He carefully picked it up and started to read the entries. He couldn't believe what he was reading! It seemed like Sans had been working on something dangerous and powerful. His eyes widened as he read the last entry. It was about a serum that was supposed to change someone into someone better. "What the-" He whispered to himself. Sans never told him anything about a serum. Sans is usually very excited to show off his work. Does the serum have anything to do with Latch? And if it does, what did that mean for Sans?
Suddenly, a yellow lizard monster walks in. "Oh. Hey there, Papyrus," she greeted him warmly. "Is Sans around? I need to speak with him about something important."
Papyrus shook his head. "Hello, Dr. Alphys, no, he's not here. I was just looking for him too. I think he might be in trouble." He explained, his voice filled with worry. "I found his notebook, and it seems like he's been working on something dangerous."
Alphys' eyes widened in surprise. "Really? What kind of dangerous thing?" She asked, worriedly.
Papyrus hesitated for a moment before showing her the ripped page in Sans' notebook. "It's about a serum that he was working on. It seems like it's supposed to change someone into someone better, but..." He trailed off, not sure what to say next.
Alphys took the notebook from Papyrus and quickly skimmed through the pages. Her face paled as she read the entries. "This can't be good." She muttered under her breath.
Meanwhile, as Latch continued to walk through Waterfall, he suddenly stopped in his tracks as he felt a strange feeling, a feeling that meant his time here was soon over, and he would return to his boring life and go by the name of Sans once again. As his fingernails lost their sickly black colour, he knew he needed to hide. As he was looking, he found a somewhat comfortable spot behind a bush, away from any prying eyes. He waited for a moment, making sure no one was around, before slowly changing back into Sans. It was painful, like being ripped apart from the inside, but eventually, the transformation was complete. He was once again Sans, but this time, in some unfamiliar clothing. He gasped for air, trying to catch his breath as he looked around. He didn't know what had happened, but he knew he had to get back to the lab. He had to find out what went wrong. As he started walking, he heard voices coming from ahead. He recognized one of them as Papyrus's.
Sans quickly ducked into a small cave, behind a waterfall. He didn't want Papyrus to see him like this. He squinted his eyes, trying to see behind the rushing water, watching as Papyrus and Dr. Alphys walked past him, deep in conversation. He could barely hear their conversation, but he caught a few words here and there. Something about him being in trouble, and a serum that was supposed to change someone into someone better. His heart sank as he realized they must have found his notebook.
"I'm telling you, something's not right," Papyrus insisted, his voice shaking with worry. "There's this new skeleton, Latch, and now Sans' disappeared. I'm afraid something might have happened to him. Skeletons don't just appear out of thin air."
Dr. Alphys sighed heavily, rubbing her temples. "I don't know what to think," she muttered under her breath. "But we have to find Sans. If he's in danger, we can't let him stay in danger."
Sans watched as the two monsters continued on, their figures fading into the distance. He was shook to his very core. He knew he had to get back to the lab and find out what had gone wrong with his experiment. But how? At least his hiding spot gave him plenty of time to think.
Suddenly, a thought occurred to Sans. He remembered he could teleport. It was one of the few things he could do without his potion. He snapped his fingers, focusing on the lab. A bright flash of light later, he reappeared in the lab, his heart pounding in his chest. He looked around the lab, his eyes darting from one end to the other. Everything seemed to be in its place, and he took a sigh of temporary relief. But as he scanned the room one more time, that's when he noticed it - the vial he left on his desk was missing. His heart sank. Had Papyrus stolen it? What if he'd already taken the serum?
Sans quickly changed out of Latch's clothes, not wanting to be caught wearing them. He needed to find out what Papyrus was planning to do with the serum. With a deep breath, he grabbed his lab coat and prepared himself for the worst.
Meanwhile, Papyrus and Dr. Alphys had spent what seemed like hours combing through the Underground, searching for any sign of Sans. They'd checked every nook and cranny, but there was no trace of him. Papyrus was growing more and more worried with each passing minute.
"Papyrus... maybe we should stop for a minute." Alphys told Papyrus, seeing the exasperated look on his face. "We've been looking for Sans almost all day, and you're starting to look exhausted."
Papyrus argued, "But what if he's hurt or something? We can't just give up on him like this!" He pounded his fists against his tiny chest, tears welling up in his eyes.
"Don't think of it as giving up, think of it as just taking a break. We'll keep looking for him as soon as we get our strength back up." Alphys tries to calm him in a gentle soothing voice.
Papyrus calms down, taking a deep breath. He knows Alphys is right. He can't keep searching like this; he'll only make himself more exhausted and less effective. "Okay... We can go back home and rest for a bit. But as soon as we're ready to go, we'll keep looking for him."
When Papyrus and Alphys returned to the brothers' home, they found Sans frantically searching through the entire house, the house looking like a complete mess as a result. His face looked tired and anxious, and he seemed to be muttering to himself. Despite the mess, Papyrus beamed with happiness.
"Sans! You're okay!" He rushes over to hug his older brother, relief washing over him. "We were so worried about you!"
Sans returns the hug, his mind still on the missing vial. "Yeah, I'm okay," he mumbles, his voice sounding distant. He gently pushes Papyrus away and looks him in the eyes. "But listen, I need you to tell me where the vial is. Do you have it? Alphys, do you have it?" He looked more and more anxious and afraid each sentence he spoke.
"No, I don't have it," Papyrus replied, his eyes widening in confusion. "Why would I have it? I haven't even been in the lab for hours." He looks at Alphys, who shakes her head, confirming she doesn't have it either. Sans feels a surge of panic as he realizes the vial is still missing. He takes a deep breath, trying to calm himself down. He turns to face away from his brother and Dr. Alphys, his expression hardening. "The vial. It's gone. Someone took it," he says, his voice shaking with rage and fear. He makes a beeline for the door, only stopping when Papyrus grabs his arm. "Wait, Sans! Where are you going?" Papyrus asks, panic rising in his voice. "Let me come with you!"
Sans shakes his head, his eyes darting around the room. "I can't... I have to find it. Alone." he says, his breathing getting heavier. He pulls his arm away from Papyrus and dashes out the door, leaving his younger brother and Alphys confused and worried.
Sans' mind raced with panic and fear. As he ran, he thought about who might've done this. "If the vial was taken directly from my lab, then it must've been someone from Hotland, Papyrus didn't say anything about a third person with him, so someone must've snuck in, someone who could squeeze through tight spaces, someone small, someone like a... A SPIDER!" And so, the first person to interrogate was Muffet.
As he arrives at Muffet's lair, he sees her sitting in a web feeding her pet. He takes a deep breath, trying to calm his racing heart. "Muffet, what have you done with my vial." he says sternly.
Muffet lightly chuckles to herself. "I don't know what you're talking about dearie~" She crawls down from her web to talk to him from a better stance.
Sans narrows his eyes, trying to keep his anger in check. "I'm not asking, Muffet. I know you took it. Now where is it?" He clenches his fists tightly, ready for any answer.
"Oh I didn't take it," She said, taunting him. "but maybe one of my spiders did." She gives a smug grin and guestures toward and empty hallway as hundreds of spiders emerge and begin to surround him, most of them holding various items and ingredients. "I sent them on a hunt of sorts, I do need ingredients for my various delectables you see~"
Sans feels his blood boil as he looks at all the items the spiders are holding. He knows Muffet is trying to provoke him, but he can't let it go. "Fine, fine. Just tell me which spider has it, I'd like to have my stuff back." He tries to keep his voice steady, but he can feel his heart pounding in his chest.
Muffet tilts her head to the side, her eyes gleaming with mischief. "I think you know better than to try and force one of my spiders to talk, dearie~" She smirks, watching as Sans's anger grows.
Just as Sans is about to lose his temper, Papyrus and Dr. Alphys suddenly burst into the lair, their faces red and their breathing labored. "Sans!" Papyrus gasps and waves. "Hi!"
"...Hi." Sans awkwardly waves back. "What are you doing here?"
"We thought we could help!" Papyrus yells, him and Alphys still panting.
Muffet smirks, her gaze shifting between Sans and the two newcomers. "Oh? And how do you intend to help, little ones?"
Papyrus finally catches his breath "By telling you to give him back his potion thingy!" He says, dramatically pointing at her.
Muffet raises an eyebrow in confusion. "Potion?" She asks, taken aback. She looks at Sans, who slowly turns his head to look at her with an unwavering stare.
"You didn't know?" He says in a hostile manner. "What did you think it was?! You've had me search all over the underground looking for a vial, that YOU stole from me, and you didn't even know WHAT IT WAS?!" Sans cried out in anger.
Muffet's pet makes a low growling noise as the situation escalates. Muffet coughs, trying to regain her composure. "I-I assure you, Sans, my little spiders meant no harm. They didn't know it was so important. I'll have them return the... item. In exchange, however, I must insist on some sort of payment."
"Payment my asshole, you stole MY SHIT!"
"Sans, calm down." Alphys says, placing a hand on Sans' shoulder. "We need to think about this logically."
Before Sans can shout out anything else, He feels a little tap on his leg. It was a little tarantula spider holding up a vial in its two front legs. It seems sad. Sans' expression softens. He kneels down and gently takes the vial. The little tarantula crawls on his hand and up to where his ear would be. "I'm sorry." It whispers. It crawls on the back of his neck and onto the back of his other hand.
Sans stands up and looks at the spider, a gentle smile on his face. "Well, thank you, little one." He says softly, the tarantula seems to cheer up a little. Sans shamefully nods to Muffet and walks away, the spider crawling down his body and onto the ground.
"I'm sorry my brother acted kinda mean. He's uh, really protective of his work." Papyrus apologizes to Muffet.
Muffet nods, still a bit tense but understanding. "Um... It's alright. As long as we can settle this peacefully." She says, looking at Sans who is already far away from them.
Muffet crawls back onto her web, her pet being a lot calmer now. She pets it as the trio walk away.
"I'm really sorry about that, Muffet. I wasn't myself at the moment. Thank you for returning it." Sans says, his voice still a bit shaky.
As they walk away, Sans gets to thinking about what just happened. He can't believe he just lost control like that. He was always so careful, always so meticulous, and now this. He shakes his head, trying to clear his thoughts. As they approach the lab, Sans parts from the group, needing time to think. "You guys go on ahead, I'll stay here."
Papyrus stops for a moment. "You sure? I was planning to make us something special when we got home. A sort of "I'm glad you're alive" gift." he chuckles lightly before waiting for Sans' response.
"No, no, you go ahead. I'll meet 'cha home." Sans says, smiling weakly. "You deserve a break. I'll see you later."
Papyrus nods solemnly and leaves, leaving Sans alone with his thoughts. Sans sighs heavily, leaning against the desk of the lab. He can't believe what just happened. He feels like he's lost control of everything, like his life is spiraling out of control. He knows he needs to figure out what to do now, but he doesn't know where to start.
Sans considers getting rid of the serum, never giving this whole situation another thought, leaving this whole thing to fade away in the back of his memory like a stain on a sweater. But... He begins to really think about what the serum was intended for. The serum was supposed to turn me into a better version of myself. he thought. so, does this mean that Latch is... just me? Just me if... I ever decided to embrace who I really am? Is this really who I am? Is that what 'being better' is? He grows more and more unsettled each moment. As he stands there, lost in thought, he starts to remember the feeling he had before the transformation. It was a feeling of emptiness, a feeling of being unfulfilled. Maybe this new... entity is what he needed all along. Maybe this is the key to unlocking his true potential.
Suddenly, Sans hears a voice, a voice that didn't seem to enter his ears, but one that seemed to come from his very own mind. It's deep, sinister, and yet strangely familiar. "You know," the voice begins, "I'm not so bad. You just haven't given me the chance to prove myself."
Sans shivers slightly, feeling the presence of the entity inside him. He turns slowly, trying to keep his composure. "What do you want?" He asks, his voice shaking slightly.
Latch chuckles darkly, his form appearing as a reflection in the full-body mirror on the side of the desk. "I'm not here to hurt you, Sans," he says, his voice echoing in Sans' head. "I just want to be free! I was only out for a couple hours, I barely even got to see the rest of the underground!"
"And why should I trust you?" Sans demands, his voice wavering. "You could just as easily take over my body permanently and leave me... like you!"
Latch sighs, stepping out of the mirror. "Sans, I know you're scared," he says, his voice taking on a more soothing tone. "But this isn't about hurting you. It's about finding my own path. You of all people should understand that!"
Sans narrows his eyes, feeling a twinge of anger at the mention of his own creation. "I... I suppose you're right," he mutters, turning away from the mirror. "I can't just abandon you. You're a part of me."
After a long moment of silence, Sans finally speaks up. "Alright," he says, his voice trembling slightly. "I'll let you out, but only at night. When everyone else is asleep. And you have to promise me that you'll stay out of sight."
Latch smirks, feeling proud he managed to get what he wants "Deal," he says, his voice low and confident. "But you have to promise me one thing in return."
Sans raises an eyebrow, suspicion clear in his eyes. "And what's that?"
"You have to let me get into trouble," Latch says, his voice taking on a playful edge. "I need to explore my... newfound abilities. And who knows? Maybe I'll find something useful for us both."
Sans hesitates for a moment before nodding. "Fine. But if anything goes wrong, I'm blaming you."
"Of course, of course... Shake on it?" Latch extends his incorporeal hand out for Sans to shake.
Sans looks at the hand warily before taking it. As soon as their palms connect, he feels a cold sensation run through him. As Latch gives a crooked grin, Sans wonders if he made the right decision.