Chapter Text
So here they were.
No one knew just how Sans had been taken over by a flower, not even Papyrus. No one had even known that it had happened, until the flower had made the mistake of trying to hurt Papyrus. Sans had broken two ribs resisting, and Papyrus had gotten away.
Word had spread from there. A lot of monsters listened to Papyrus, now that he was the only remaining member of the Royal Guard. A lot of monsters liked Sans. Papyrus' first priority had been, quite simply, to make sure that the flower didn't use his brother's face to hurt anyone.
It was too early to know for certain, but signs seemed to point to his success in that regard. Sans had been denied any easy targets besides Papyrus, who was somehow only just ever a few steps ahead. So Sans - or maybe the creature taking root in his body, or maybe both of them acting together for very different reasons - had chased after Papyrus. The flower wanted someone to hurt. Sans wanted his brother's help.
So here they were in Hotland, and with its long, narrow paths brightly lit with lava below, there was nowhere for Papyrus to go but onwards, nowhere for Sans to go but towards. The flower buried deep inside his skull called out taunts all the while, that almost sounded as though they came in Sans' voice. Almost, but not quite - the words echoed with the harmonics of something cold, cruel, and evil.
"this is probably the most your trashbag brother has ever moved in his life, papyrus! and he's tired, he's so tired. i can feel him trying to hold me back from crushing your stupid grinning skull under his feet, and guess what? it's not going to work this time."
Papyrus didn't reply. Papyrus only ran, fast but never quite fast enough.
"but it's your own fault! do you know why it's been so easy for me to chase after you? it's because sans still wants to . he wants you to help him, and you keep abandoning him! you left him back there in the ruins with me, and now here we are again!"
Here they were.
And Flowey didn't realize until too late that the sound of the floor beneath Sans' feet had changed.
He looked down to see tiles, in shades of grey and white. He looked up to see Papyrus, now standing and facing him just a few yards away, looking back at him and grinning.
"w-what's going on?" Flowey asked, and this time the question came entirely in Sans' voice. He hadn't been lying, after all - Sans really was so, so tired, nothing more than a whisper in the back of his own head where Flowey had ruthlessly beat him into a corner. The tattered scraps of the skeleton's soul really were trying, straining, fighting to hold Flowey back from Papyrus. Yet the raw and bleeding center of him was nevertheless screaming in the same breath for his brother to come and help him.
Those tattered scraps of soul grew warm and bright and worryingly strong, as Papyrus struck a dramatic pose and laughed.
"FLOWEY," said Papyrus. "OF ALL THE THINGS YOU'VE DONE, I THINK THIS MIGHT BE THE MOST DISAPPOINTING. YOU REALLY WERE MY FRIEND, ONCE - BUT AFTER ALL THE TIME WE SPENT TOGETHER, YOU STILL THINK THAT I, THE GREAT PAPYRUS, WOULD EVER ABANDON MY BROTHER? NYEH-HEH-HEH! THAT IS THE MOST RIDICULOUS THING I'VE EVER HEARD - AND I'VE HEARD EVERY ONE OF SANS' PUNS!"
Sans had been very, very quiet for the last long while, which had left Flowey confident that he would soon have complete control of the body. It had even been growing steadily easier to pick through Sans' memories, to use them for his own as he would.
In his shock, in his hope, Sans' defenses were suddenly even weaker, and Flowey shared his realization all in a rush.
we're on a puzzle we're on a puzzle maybe he really does have a plan...
Flowey took another look at the tiled ground, feeling panic boiling up through his roots. They were facing off against Papyrus, on a puzzle.
Uh-oh.
He didn't want to turn and run. He'd been running long enough, and even if it had let him lock down control over his new body, Flowey had only ever wanted this body so he could have some new and interesting ways to kill people. Or, more specifically, so he could make his old enemy kill people in new and interesting ways.
But maybe he could bring this body to run a little further after all. Flowey turned Sans around and started back the way they'd come.
"Nuh-uh!"
There was a figure with a gleaming smile and an equally gleaming spear held in hand, standing back at the other end of the puzzle. "Alphys!" Undyne called, racing forward. "Hit the switch!"
Then a voice called back, faint on its own, but echoing along the narrow path in the vast cavern. "Got it!"
There was the sound of a switch being flipped, and the tiles beneath their feet exploded in a flashing blaze of various colors, red and green and blue and pink and black...
wait, Sans wondered. what did black tiles do?
Don't ask me, idiot! You're supposed to know about your brother's stupid puzzles!
He felt Sans smile. He felt the threat of the future crawling on his stolen back. guess we'll find out together.
Flowey looked forward and back, still held safe for the moment behind Sans' eyes. Papyrus and, apparently, Alphys blocked the way forward. Undyne had vanished from the path behind, but that didn't necessarily mean anything, knowing even just what he knew about Undyne. Could he make it back there and off the tiles before the puzzle settled?
Jump jump jump! Listen to me, this is my body now...
Appallingly, Sans managed to dig in his heels. He didn't manage much - Flowey still managed to jump, but then it was like tripping over his own roots, so that when the world blurred back into focus he was still on one of the tiles at the very, very edge of the puzzle, just as the puzzle itself settled into being.
The tile beneath his feet darkened to black. Flowey looked back up the path to see Papyrus racing back towards them, effortlessly navigating the puzzle itself. Or so Flowey assumed, having no idea how the puzzle itself worked. Taking the path back that way would require going through Papyrus.
Not that that was necessarily a problem. Flowey was willing to do that, willing to end this right now if Papyrus was going to race headlong into his vines. Sans was so tired, keeping Flowey here had left him as little more than a fly crawling along Flowey's stem. Now was the time. Now is the time.
Watch. For all the trouble you've caused me, for all the times you've defied me, you will watch while I do this. You will watch him die by your hand and feel your LV go up from his dust!
Flowey tried to lunge forward, bringing vines looping up and over the pathway...
...only to be stopped dead in his tracks, feeling Sans' soul turned green, and Sans' body rooted to the tile as a result as surely as any of Flowey's roots could have done. A shield appeared on the skeleton's arm. "what?!"
A tile two up and three to the right was filled with clear blue water. A shadow rose up through it and surfaced with a splash, and Undyne was there, her arms braced on the pink tile in front of her. "Hey, loser! Going somewhere?"
"WITH MY BROTHER'S SOUL TURNED GREEN, HE IS GOING NOWHERE AT ALL...EXCEPT FAR AWAY FROM SANS!"
"oh, yeah?" Flowey demanded, raising his arms and summoning a flurry of bones at the ready. "what are you gonna do? beat me out of him? i'm sure i don't need to remind you how much HP your brother has, papyrus! even if i let you just stand here and hit me, you'd only be hurting him!" He grinned, as wide as he could, until Sans' skull hurt with it. "so go ahead! come and get me! sans would be just fine with that - do you have any idea how long he's wanted to die just to get away from me?!"
it's okay papyrus i understand i understand you have to keep everyone safe i don't want to hurt anyone...
But Sans had to watch, as Flowey sent a line of bones spinning in two arcs away from him, one aimed at Papyrus and one at Undyne. It didn't do much to them, not yet - Undyne ducked down beneath the water, and Papyrus blocked each of Sans' bones with one of his own. But it drove the point home for Sans that he was no longer strong enough to stop Flowey.
"You're right," Undyne said, surfacing with barely a breath. "If either of us managed to hit Sans, he'd die. He's kind of a wimp like that - no offense, Papyrus."
"NONE TAKEN. AND I'M SURE MY BROTHER AGREES."
she's got a point.
"But that's only the damage his soul could take. His body's a bit more resilient than that."
Flowey brought a rain of bones tumbling down towards the water. Rather than hop to another tile, Undyne ducked down beneath the water again, darting this way and that within the confined space. But they saw, from the way the darting blur faltered and twisted for a moment, that she didn't quite succeed.
"so you plan on attacking me without attacking me? brilliant plan, geniuses!"
"THAT IS EXACTLY WHAT WE PLAN ON DOING!"
Undyne surfaced once more, not without a wince, her arm visibly dragging a bit. "Papyrus. Tell him about the puzzle."
"RED TILES ARE IMPASSABLE. YOU CAN'T WALK ON THEM. GREEN TILES ARE ALARM TILES..."
"Papyrus. Tell him about the black tiles."
"OH, RIGHT! BLACK TILES ARE WILD CARDS! DOCTOR ALPHYS CAN PROGRAM THEM TO DO ANYTHING THAT MIGHT BE REQUIRED!"
"And Sans' old friend Grillby had some ideas about what might be required." Undyne's gaze grew hard, and her smile was as sharp as her spear. "You stopped by and said hello to Grillby, didn't you, you sack of fertilizer food?"
They both remembered. For just a moment, the thoughts of Flowey and his prisoner were entirely in-line for entirely different reasons.
'I am aware of what I would have to do to get to you through Sans. Bone is more resilient than you'd think...but plant matter is another matter altogether.'
No.
yes.
In the end, he hadn't gone through it with it. In the end, he'd still been too afraid of hurting his friend to act, and they'd made him pay for it. But a machine couldn't have hostile intentions. A machine could damage the body, but not the soul. HP wouldn't enter into it - it was just a matter of whether Sans would burn to ashes before Flowey. If he did, his soul would break anyway, of course, but...
"Light him up, Alphys!" Undyne called.
Flowey put all his effort into Sans' voice, as he felt the ground beneath his sneakers grow warmer and warmer. "papyrus, w-wait! please, you know i'm not strong enough to take this. there must be another way, please, you're my brother, why won't you protect me...!"
Papyrus folded his arms and hunched his shoulders, but he didn't look away. Undyne looked to him, her expression flickering with sympathy for a moment. "Papyrus, you know you don't have to watch this..."
"YES, I DO. BECAUSE I WANT SANS TO KNOW THAT I'M HERE FOR HIM. I WANT HIM TO KNOW THAT I KNOW THAT HE'S GOING TO BE OKAY, AND WHEN ALL OF THIS IS DONE, I'M GOING TO TAKE HIM HOME AND JUST THIS ONCE, I'LL EVEN LET HIM EAT ALL THE TERRIBLE AND UNHEALTHY FOOD HE WANTS."
He looked up at Sans, looked through Flowey to his brother's soul where it was trapped in a prison of thorns and vines, and Papyrus smiled. It wasn't his usual grand, dramatic gesture, but the expression shone with just as much sincerity and open, genuine hope.
Flames sprouted from the tile beneath their feet, licking higher and higher, and Flowey felt his leaves begin to scorch.
Sans, however, had never felt stronger. There was no one more determined than those who had nothing left to lose, and now they couldn't look out at the world without seeing flames and it was hot, it was so, so hot, their bones were scorching and their roots were burning...
Flowey dug his thorns into body and soul. Jump!
Sans felt the pain and Flowey heard him laugh. no. you want me? stay here and burn with me.
You really think you're strong enough to take this? You really think they won't burn you alive, even if they don't mean to? No. You're...you're just bluffing! You won't really let yourself die here...will you?
do you really want to make that bet with me, kid?
Papyrus didn't look away. He didn't so much as blink. Undyne heaved herself up and out of the water, and hopped over to stand beside him for the sake of resting a hand on her friend's shoulder. He leaned a little into her touch, but gave no other acknowledgement. Even he probably couldn't have made himself heard as Flowey screamed, and made Sans scream with him.
* * *
“Hi there.”
It was…a voice, and it was a familiar voice. The shadows at the edge of the passageway looked like they were the right shape. But it wasn’t Sans’ voice.
Papyrus strode nearer anyway. Whoever was down there, he couldn’t see their eyes, but he could feel their gaze all the same as they watched him approach. It couldn’t have been Sans. Sans’ eyelights weren’t as bright as his brothers’, but they were still visible enough even in weak light.
“I’m your best friend.”
The passageway opened up into a small room of sorts just a few more feet along. Light shone down from above, grey and weak and strange. Despite himself, despite the urgency and the sense of danger that even he could no longer ignore, Papyrus looked up to see the source of it.
He felt the space between his ribs tighten after a moment of wonder. The sky. They were somewhere beneath a hole that opened up into the outside world, and the source of the light was coming from outside. It wasn’t just light, but rain, too, like the sort that fell eternally inside the caverns of Waterfall. Had this hole always been here? Had he always been this close to seeing the sky, just blocked by the doors that had sealed away the Queen?
There was light shining from within the cavern as well. It seemed unnaturally bright in contrast to the light from above, especially since it shone a brighter gold.
His gaze slid down, and other details made themselves apparent. Like…vines. There were lots and lots of vines, creeping up the walls of the cavern, extending out from…
“…SANS?”
“Sans,” his brother agreed with an easy nod, in a voice that wasn’t his. He spread his arms, grinning widely, as though he’d just performed a good prank. More vines were visible beneath his shirt as he moved, peeking out of his sleeves, all but covering his shoes. “The skeleton! No use fighting, you’re mine now.”
At first, Papyrus thought wildly that his brother who wasn’t his brother was talking to him. Then he saw that Sans’ right arm was twitching, straining as the plants wound tighter. Vines were creeping out of his empty right eyesocket. For a moment, just a moment, the smaller skeleton shuddered and shook and panted with exhaustion and visible pain.
This was Sans, and Sans was trying to reach out to him. But something was holding him back.
“SANS!” Papyrus cried, reaching back, wanting to help but still too shocked to know what to do. If this were anyone else, anything else, they would already be pinned to the ground, battered by bones, but it wasn’t anyone else.
“I just want to make sure…that you know…” the voice continued, not Sans’ voice but speaking from inside Sans and so, so familiar anyway. Distracted. The voice sounded distracted as it…as it…
His brother’s struggles stilled once more. Wildly, Papyrus found himself thinking of the last time one of his favorite action figures had run out of batteries, the way it had sputtered and stumbled before growing inevitably still. He shook the thought out of his head, but the reality of the matter was little better.
Vines were creeping up out of the top of Sans’ shirt, now, twining around his spine. “...you’ll never see him again.”
“NO!” Papyrus yelled, defiant and despairing in the same breath. No amount of hesitation or concern could have held him back, then - he leapt, swiping his hand through the air to summon up his blue attack. It was the only thing he could think of to do that wouldn’t hurt Sans but might hurt this thing and he had to do something .
Unfortunately, paralyzed with horror and dread as he’d been, the invader had been acting. Roots and branches had sprouted up from the ground, over his boots, tangling and tripping him in place just as they had Sans. It hadn’t been long enough to actually restrain him from moving, but it threw him badly off balance, forcing Papyrus to spend precious seconds correcting himself to avoid collapsing in an ungainly heap on the ground. The ground was clearly a very unsafe place to be right now.
Those precious seconds cost them both dearly, as something came striking out of the darkness to catch him hard across the front, sending him slamming forcibly into a wall of the cavern.
And then Papyrus felt his soul turned blue instead, felt his own personal field of gravity invert and twist itself so that his soul now believed the wall to be the ground, so that he was quite effectively pinned. It was a mastery over that particular attack that only Sans himself had ever demonstrated.
Sure enough, when Papyrus’ vision cleared, it was to see that Sans’ left eye was flaring bright, and one arm was extended out towards him, bony fingers splayed - at least, he’d been forced and dragged that way by the roots and vines entwining him tightly. Maybe it was the impact talking, but Papyrus thought they almost seemed to be…wriggling.
“Your brother…he belongs to me, now.”
Papyrus struggled and strained against the force keeping him pinned, but Sans had always, always been the stronger of the two of them and the creature that was using his body like a toy seemed to be just as strong. All he could think to do in that moment was call out again to Sans for help - his brother was still awake, still aware, he’d seen it…
…and then, this time, Sans answered. Several things happened in quick succession, and Papyrus missed most of them as his soul suddenly oriented itself properly, only to leave him collapsing in an ungainly heap on the ground anyway. When he looked up, Sans had stumbled several steps back. He stood hunched over and crouched, one hand pressed tightly to his head, the other unmistakably scrabbling to grab ahold of the vines extending out of his eye…
“papyrus…run…stop it! You know you can’t beat me please stop it!”
Papyrus did run, but he ran once more towards his brother. Unfortunately, the conflict between Sans and the invader was making the cavern dangerous. The roots that had extended out of the ground were twitching and thrashing in apparent agitation, vines creeping all the more quickly over the rock, chunks being torn out of the walls as Sans’ powers seemed to flare in every direction at once. The ground was trembling beneath his feet.
“run…” Now the noises Sans was making in his own voice sounded less like gasps of pain and more like sobs. Now the voice that wasn’t Sans’ sounded a little more like Sans’.
This was all familiar, this was all so familiar, but why, how…
Papyrus summoned bones up out of the ground to try and make some steady footing for himself, but Sans made them vanish out from under his feet, and Papyrus fell once more.
“If you don’t stop fighting, I’ll kill everyone you’ve ever loved. And I’ll use you do to it!”
Papyrus managed to make it up into a half crouch without being pitched over or pinned down again, but when he looked up desperately at Sans, he felt himself paralyzed anew by fresh horror.
Sans’ left eyesocket was no longer empty. Something was emerging from it - blooming. Golden petals blossomed.
“Won’t that just be peachy?”
And, as Sans shuddered and sobbed and whimpered helplessly, Papyrus found himself looking into the cheerily smiling face of a familiar golden flower.
It winked back at him, and either Sans or Flowey swiped a hand through the air, sending Papyrus tumbling back towards the mouth of the cavern with a yelp of pain before he could have possibly thought of defending himself. He knew the attack had come from Sans when it tried to push him further - this time, Papyrus was able to push back, and at least stand firm to look back at his brother through the swirling clouds of dust and leaves that filled the cavern, to look back and plead as he couldn’t remember having ever done before.
“SANS, I WON’T LEAVE HERE YOU LIKE THIS! I…I CAN’T…!”
“papyrus, i can’t fight it off forever!” It was the most Sans had said at once since this had begun, and it clearly cost him dearly. Flowey took the momentary lapse in Sans’ focus to press his own influence. For a moment, both the face of his flower and the face of his brother wore identical looks of pain and gritted effort.
“he’s going to use me to kill you, please get out of here, please, please …”
Papyrus heard something crack inside Sans. Maybe it was something in his body. Maybe it was something in his soul. Sans arched back for a moment as though his spine were about to snap…and then he let out a soft, airless little sigh, and slumped forward instead.
Then Flowey laughed, and Sans had no choice but to laugh with him. “heheheeheeheeheehee. My, my. You held out to the last, just to warn your brother.”
Sans’ body lifted its head. Flowey had retreated back into the depths of Sans’ skull, but Papyrus held no delusions that it was Sans who was smiling at him much, much too broadly. The tiny golden flower winked at him with his brother’s eyes, as though they were sharing a private joke at Sans’ expense.
“That’s so cute…”
“SANS…!” Most people didn’t realize that skeletons could cry. Sometimes, even Papyrus forgot that they could. Their lives…his life…held so little cause for it. But now his vision was blurred with them, his cheekbones were warm with them, because there was no denying even to himself that he didn’t know what to do. Sans was his brother, Sans was tired and fragile and sad and Papyrus was supposed to be the hero who kept him safe . Yet all he could do was stand here and watch Sans in pain, obviously being torn apart from the inside out, but how could he save Sans without hurting him, too?
Was that really the only way?
And then the light in Sans’ left eye flickered one last time, a dull and smoldering ember, and Papyrus knew it wasn’t the only way even before Sans caught his breath to speak, gritting out the words in his own voice.
“if you don’t run now, he’ll get you, too. I will. I t’s no joke. ”
A rustling along the ground alerted Papyrus just in time that Flowey had been sending creepers inching towards him in an attempt to do just that. Far more brutally than he’d ever wanted to believe himself capable of, Papyrus cleared them aside with two swipes of summoned bones. More moved in almost immediately to take the place of their destroyed brethren. It was a token gesture that saved him, but did nothing to save Sans.
“…I’LL BE BACK FOR YOU,” Papyrus heard himself say. He knew in the space between his ribs that they were the right words to say, maybe the only words to say, but he didn’t want to believe that he was saying them.
Before his resolve could falter any further, before he made the mistake of looking at his brother and being deceived once again into believing that his brother would truly be looking back as anything but a prisoner, Papyrus turned and ran. He ran down the passage until his hearing told him that he’d gained enough distance on the vines pursuing him even now.
Only then did Papyrus whirl back around. His right eye flared bright, and he clapped his hands forcibly together, one on top of the other. The effort left him dizzy, but the very bones of the earth and mountain responded, slamming down from the ceiling and up through the floor to meet in the middle and block the passageway behind him, so tightly that not a breath could pass through.
Something tried anyway, scant seconds later. Something hit the barrier hard enough to send flakes of calcium tumbling to the floor. Something scrabbled at the wall in its way, and then whined: “papyrus, don’t leave me!”
The plea was convincing enough to make Papyrus sob, but then he heard Sans respond to his captor. “stop it, i told him to go, i want him to, no, I don’t…”
He could have turned and run, in that moment. Maybe he should have. Instead, Papyrus crept back to the wall of bone, pressed his hands against it, pressed his forehead against it. It was the closest he could come now to his brother. Like this, he could still hear Sans’ voice through the wall. Papyrus wanted so much to believe that it was only Flowey saying those words. He wasn’t sure he could.
“It hurts, Papyrus, help me, please, you’re my brother, you’re not supposed to leave me alone to hurt, run…”
“I’LL COME BACK FOR YOU,” Papyrus repeated, for the benefit of them both. The voice on the other side fell abruptly silent. “CONSIDER THAT A PROMISE, FROM THE GREAT PAPYRUS.” He tried to dash the tears from his eyesockets - there was too much to be done, now. There was too much at stake. “CONSIDER THAT A PROMISE…FROM YOUR BROTHER.”
Then he did turn, and then he did run, and the sound of fingerbones scrabbling and scratching at the walls haunted him long after he passed out of earshot.
Sans…I left him alone. I left him behind. I abandoned him, I shouldn’t have left him behind, Papyrus thought to himself, as he stumbled down the longest hallway in the ruins. The mad energy that had first fueled his flight was draining out of him rapidly, leaving him unsteady on his feet, his vision blurred with shock and tears. One more step, and his resolve nearly broke. He nearly went back.
Another step, and Papyrus built his resolve even higher.
But he knows why I did.
I’m his brother. I have to protect him.
And maybe, to do that, I have to leave him behind. At least he was somewhere secure. At least, if he held Sans in one place, the bit of his brother that was still his brother would know that Papyrus meant to come back for him. No, not just meant to come back - would come back.
To start with, there were still monsters living in the Ruins, even now. It was famliiar to them, and it was safe. Or it had been, until now. He would have to find them, he would have to gather them up, he would have to help them leave. Just in case. Sans shouldn’t be able to get past that wall, but…just in case.
Sans wouldn’t want to hurt anyone, after all. Sans never wanted to hurt anyone.
Papyrus could spare him that pain, at least, while he found people who might know how to spare him the rest.
* * *
“Look, Sans, he’s gone! Just like you wanted!”
From a stalk extending from one of Sans’ eyesockets, Flowey was able to turn and regard his new body with a bright, happy smile where it was slumped against the wall of bone. Sans smiled back at him. He didn’t have a choice.
“With no one around, you don’t have to worry about hurting anyone, right? Because if there’s no one here, there’s no one to like you, and there’s no one for you to let down! And soon, you won't have to worry about letting anyone down ever again, because there'll be no more you! I saved you, Sans.”
Slowly, carefully, he eased himself back through Sans’ eye.
“We’ll be together forever, Sans.”
He stood up, and looked down at hands that weren’t his hands…yet.
But they would do, for now.
“Just you…”
“just you…”
“And…”
“and…”
“Me.”