Papyrus actually needs to sleep sometimes, and the new Sans needs to not sleep all the time. Sans—the original one, native Sans, Sans-prime, whatever—waits until his baby bro isn't around to go in and talk to New Guy. You gotta appreciate his reliability, New Guy. He's always right where you last left him, like that sock in the living room that'll never get put away.
please let the new guy not be fallen down already, Sans thinks.
He isn't. The guy's lying in bed, pretending to not be awake, though the rattling gives him away. Sans taps on the doorframe, waits for an answer he doesn't get, then goes in and slides a couple of Papyrus' action figures aside so he can sit on the edge of the desk. He feels like a sitcom dad trying to have a talk with his troubled kid, or something, only the "kid" is a clone of him who looks like he's two minutes away from his SOUL calling it quits, and... yeah, he should just give up with trying to draw these goofy comparisons and accept this situation for what it is. He's gotten used to plenty of other weird crap in his life already.
Sans pretends to clear a throat he doesn't have, prompting the new guy to look over.
"listen. what i said the other day? that's all still true. this... situation... it isn't sustainable."
Rattlerattlerattlerattlerattle.
"what do you want? like, what would make you happy... or at least driven enough to get out of this room and DO something? that's hypocritical coming from me, i know, but it's an open-ended question. ding-dong-ditching asgore's place is a perfectly valid answer. just gimme something to work with here."
The other Sans wants to be allowed to sleep, but he's been asked a question and feels bound to give an answer, even if most of the things he wants are too abstract for asking. He wants to be the innocent person sitting in front of him. He wants to not feel the way he does. He wants his life back.
"i... wanna know if everyone's ok," he croaks. "everyone at home. wanna go home."
Sans was hoping he'd go for the ding-dong ditching. That's always fun. "ok. that's, uh, a valid thing to want. very relatable. the problem is achieving it. i dunno how things panned out for you back home, but that machine out back... i tried to get it running again. no dice, and believe me, i tried. got any other suggestions?"
Rattlerattle.
"nothin?"
"a haircut."
Overused, but it's all he can muster and the Sans of this world will gladly take a cheap joke over literal nothing, so he snorts. He folds his arms, waiting and hoping for a real answer. It doesn't come. Knowing himself, he should've expected that.
"look, sans, you gotta—" he begins.
"not gonna die on you. m'just tired."
Which of course is the third-least reassuring thing he could've said, right behind i'm so cold, mommy and hey check out this sick-ass family photo, also I'm retiring in two days. Sans waits some more, because waiting means doing nothing but with a purpose and he's down for earning free good-person points. It's not that he doesn't legitimately want to help for its own sake, he just doesn't know how, and meanwhile the new guy stares at him like he's already totally dead inside. Looks close to dead on the outside, too, with his SOUL all banged up like that. It's like looking into a funhouse mirror from hell, or that scene in a sci-fi movie where the hero's future self crawls in and warns them to turn left instead of right that morning, or to not trust the alien visitors, or whatever.
Sans slides off the edge of the table and is just about to leave when the new guy sits up. "wait."
"yeah?"
"i've... been wonderin'," New Guy mumbles, looking down at a half-full cup of no-longer-hot hot chocolate Papyrus left for him. "if an entity takes control of somebody and it, uh... while it's wearing him, it... fools around with people it thinks are... cute, like, other skeletons, or humans, whoever... and it's using him to do that... is that... a crime? the. the aspect that's... aside from just the body-snatching. the smooching, and... all, all that stuff. that part."
Leaving Sans at a loss isn't easy, but the question flies straight in out of left field and bashes him in the face; he starts to wonder if the guy is speaking euphemistically and then decides that he deeply and profoundly doesn't want to know. "oh... jeez, dude. jeez."
The new guy waits for an answer.
"i, uh. i dunno. that depends on what the person in question thinks, i guess."
"i'm asking what you think."
Sans picks up a couple of Papyrus' action figures and sets them back into place, then changes his mind and rearranges them into headstands and ballet poses.
He steps back to admire his handiwork. The other guy is still waiting, watching him.
Sans squirms. "hey, you really sounded like you had your heart set on getting outta here, so... i guess we could take another look at that thing out back. see if we can get anywhere with it. two boneheads are better than one, right?"
Neither of them can fix the machine, no matter how hard they try.
Nobody can.
The excursions to the shed got the new Sans out of the house by about 20 feet, and the repair efforts on the machine only reaffirm the reality that Sans is probably never going home for real, but it seems to flick a switch somewhere inside his skull.
He follows his twin out to the sentry stations most days. Usually it's the one in Snowdin, but there are the stations in Waterfall and Hotland too. It doesn't make a difference to him as long as he isn't alone. The Sans of this universe sits and reads car magazines and inflicts bad jokes on anyone who happens to pass by, or else he offers to sell them a hot dog/cat/animal. The new Sans sleeps.
On the days when Papyrus goes to hang out with Undyne, the new Sans goes with him instead, to his adoptive brother's delight and Undyne's confusion. Papyrus' whispered story about a mind-controlling squid thing with a fondness for neon colors sounds like something his brother would make up just to mess with him—Sans figuring out how to do a weird trick with his eyelights and managing to be in multiple places at once isn't even that implausible—but she's seen the two clones together at the sentry stations. As the captain of the royal guard, she does not like the idea of universe-jumping mind-control creatures being able to pop up in the Underground whenever they please; as a monster, Sans' eye situation creeps her out. Papyrus seems confident that the new Sans is okay, though, and he knows his brother better than anyone, so she tentatively accepts his explanation. She doesn't have much of a choice. And so bone attacks and energy spears clash in the training sessions, and Papyrus and Undyne try cooking some popsicles and blow up her oven, and the new Sans sleeps through everything, fiery explosion included.
Papyrus takes his brother's kind-of-sort-of increase in activity as evidence of recovery. He has no issue with Sans borrowing his room per se, but Sans would sleep for 20-hour stretches if Papyrus let him, and he barely eats, and he only sort of responds when Papyrus wakes him from his nightmares and tries to comfort him, and there's typical lazy Sansly behavior and then there's... that. Nothing bad could possibly happen to Sans now, not with his brother taking care of him, but it's hard not to feel a little worried. Or a lot worried.
But Sans is improving! Papyrus wastes no time in proposing that they build a third bedroom in that extremely convenient empty space in the hallway between his room and the one belonging to the first Sans. Sans #1 has no opinion as long as he doesn't have to share his room with the other him. In the meantime, their new brother moves from the racecar bed to the couch, which is far from ideal, but any kind of change seems like a good thing, so Papyrus will take whatever progress he can get.
In theory, Sans is sleeping on the couch until they get the bedroom situation figured out; in reality, he sleeps at the sentry stations or at Undyne's place and survives the nights as best he can. He's too exposed in the living room, it's too open and too dark. The TV is a decent distraction, but there's hardly anything on late at night except reruns of Mettaton movies which involve way more glitter and clown-barf outfits than he feels like seeing. He lies awake and listens to the obnoxious music and shivers. Without sleep to numb him or Papyrus to help him, he can hear ugly thoughts lurching in the basement in his head.
Was he that thing's first host, and if not, how many unlucky bastards did it torture to death before him?
Down one step.
Why did the thing choose him? For some unfathomable reason, he feels like being taken over might not have been against his will at the very beginning, but he has no idea why he would've consented to that. Maybe the parasite itself told him so, just to fuck with him even more than it already had been, because his mind was too fried for him to remember it wasn't true. He still doesn't remember and the thing is dead, so now he'll never know.
And one more.
When he still had the strength to fight, he tried to take back control, he tried to use the glasses to signal for help. Somebody had to have seen. Somebody had to have realized what was going on; that thing made no effort to mimic his actual personality and he refuses to believe that Alphys was the first and only person to see the truth. Those other guys who saw him and especially those who saw him without the glasses, saw his cracked SOUL and an eye that didn't belong to him, those guys sure as hell knew. They knew. They had to know. They could've saved him, and it all could've been over so much sooner, he could've gone home—but it wasn't, he can't, they didn't, it never had to get so bad but it did. Fucking selfish bastards. They were all complicit, sure he's lazy and he's let people down but never so badly as that. Are they all really the same person? Some of them aren't, they just happen to look alike, but most of the guys who looked like him were him. There must be something fundamentally broken in his own psychology, an underlying disease of the SOUL that remains dormant only as long as his life stays relatively normal. The Sans from this world must already carry it. Funny, with how he handles his new double so carefully—he sees the damaged SOUL and thinks there but for the grace of dog goes i because he doesn't know yet that he's all messed up inside too. Funny. Hilarious.
please, please, he prays to no one. don't let anything happen to him. he doesn't deserve it.
The darkness keeps growing.
Did all those guys choose to do nothing out of laziness and selfishness, or was it a rational decision? When a human buys a mass-produced lamp and it breaks, they throw it away and it ends up in the garbage dump, they don't fix it. Is that how they saw him? Can he blame them? He's not useful as he is now. He's not fun anymore.
Or is there more to it than that? What did they all know that he doesn't? Did he actually let that thing take over his body? How many people has it used him hurt? Is his brother... are their friends..?
No, no, no. Stop. Stop.
The other guy's warning sticks with him: he owes it to Papyrus to not Fall Down. The local Sans and Papyrus welcomed him when they have nothing to gain in return, and if he dies, that thing wins. Right? It seems like the kind of thought that should help. If he Falls Down then Papyrus is sad and the thing wins.
Mostly he just feels like a dumb kid who's scared of the dark.
It's an especially bad night. Nothing much happened in the day before, but the screwy sleep schedule is messing with him, the machine in the workshop is broken forever, and self-hatred burns inside him like a corrosive poison. He's too weak and drained to hurt anyone except himself but—yeah, that's the point, isn't it? He prays that the other guy won't innocently wander past on the way for a midnight snack, or he's going to have some kind of screaming freakout. It wouldn't be fair. The other guy's been nothing but good to him.
He keeps thinking he sees little shapes scuttling in the corners; his darkened eye socket tingles. The minutes crawl past and he feels like he's going to explode or do something stupid. He needs someone. But it can't be the other Sans, and Papyrus worries enough. Alphys invited him to talk to her whenever he wants, but she's got her own basement full of half-living shapes lurching in the dark. Sans reaches for his phone, which isn't actually his phone—that one's long-gone—but a burner loaned by the other guy. He flicks it on, turns it off. The contact list is empty and he doesn't remember anybody's number.
He stares blindly at the TV until it cuts to a commercial for bishie cream, then slithers out from under the blankets. Shortcuts require magic and concentration, neither of which he's got, so he puts on his sneakers (actually borrowed from the other guy, just like the phone) and lets himself out of the house.
He feels like he's being watched as soon as he steps out onto the snow, a sensation which has nothing to do with Alphys' cameras. He's too vulnerable here, too easily-seen, and there's nobody else around. Or it's just paranoia maybe. He feels like he's earned the right to be paranoid. He speed-walks to the dock, and as he boards, the Riverperson hums and reminds him of the day of the week. His hands shake in his pockets.
They reach Waterfall. As Sans disembarks, the gemstones in the walls glitter like the stars he's sometimes seen in the other worlds. The parasite didn't care about stars but he did. To distract himself while he walks, he mentally rattles off the names of as many constellations as he can remember: the Pleiades, Andromeda, Cassiopeia, Ursa Major and Minor, Orion, Lyra, Aries-Taurus-Gemini-Cancer-Leo-Virgo-Libra-Scorpio-Sagittarius-Capricorn-Aquarius-Pisces, Lyra, Vulpecula...
He knocks on Undyne's door too quietly, then too loudly. When she opens up, relief washes over Sans and he wouldn't even care if she immediately decked him for waking her up. Which is good because she's not looking super thrilled.
"h-hey."
Undyne rubs her eye. She's wearing a wrinkled hoodie over an old shirt with some anime girl on it and pajama pants printed with little seahorses, and her hair is in tangles around her shoulders. "Oh my GOD, what is with you guys and showing up at my house in the middle of the night?!"
"sorry. i. just, um." Sans has had plenty of time to think and he still doesn't know what to say. He feels himself rattling; he tries and fails to get it under control. "...had a flash of inspiration for a really good knock-knock joke?"
"..."
"ok, it's not actually that. i'll scram if you want. just... ...wanted to... talk to somebody."
Undyne squints at him, sleepily trying to process this. The SOUL in his eye socket glows unevenly. Papyrus insists that it's fine and that Sans has already talked to Alphys about it, but it's distracting as hell. "Oh, it's you. Alien guy. Don't you live with Papyrus and... also you? Go bug them."
"don't wanna."
"Dude, it's three in the morning."
"sorry. just don't wanna... freak 'em out even more than i already have been," Sans mumbles. "i need to talk to somebody."
"At three in the morning."
"it's... sorry. shouldn't've turned up like this. i'll go."
That last, slightly quavery apology brings Undyne back to the first time she met Alphys and cuts through her sleepy haze. He might not be standing at the edge of a cliff, but he isn't okay.
"Nah, it's—wait." Undyne grabs for his arm before Sans can turn away, making him flinch. "You're already here, so you might as well come in and say whatever you wanted. I don't need to wake up early tomorrow anyway, so, whatever." That last part's a lie, and Undyne has to bite back a yawn to say it. "Want some tea?"
He does.
Undyne keeps an eye (half an eye? She's just got the one) on Sans while she fills the teapot and he slouches at the table like one of those beanbag stuffed animals and quivers. She first met Alphys at a dangerously low point in her now-friend's life, and now here she is with another troubled SOUL on her hands... a SOUL with huge cracks in it. If any monster is in danger, she'll help them, but she usually thinks more along the lines of kicking the crap out of humans or doing cool parkour jumps off cliffs to save people, not this emotional stuff.
"So, you gonna tell me what's eating at ya, or what?" she asks lightly.
Sans is quiet for so long that Undyne glances over to make sure he didn't just fall asleep. He's awake. He looks lost, though.
"Papyrus already told me what your deal is," she adds, bluntly but not unkindly. "The mind control thing? So, if this has to do with it, then... go ahead, but if it isn't, you don't have to explain that part."
Sans itches at the thought of Papyrus telling Undyne all about him, but he's Papyrus, of course that's what he did. "y... kinda."
Undyne waits for Sans to elaborate. The kettle bubbles.
"I told Asgore about you, by the way," she says, to fill the silence. "It seems like you need some time to decompress, or whatever, but he wants to meet you."
"m'not going to hurt anyone," Sans mumbles at the tabletop. "didn't come here on purpose."
Undyne scoffs. "Psshhht, you think we're worried about you being a threat? Hell no, Asgore's worried ABOUT you, ya bonehead. Knowing him, he's already searching high and low for a cute skull-shaped teacup he can give you."
She takes down two cups from the cupboard and pours out the tea, keeping the fish-shaped cup for herself and sliding the flower-printed one in front of Sans. His hands curl around it.
"can i ask somethin' weird?"
Undyne sits across from him. "Yeah, go for it."
"ok. uh. pretend, like, you're an... alien... kind of thing." It should sound completely goofy, especially coming from Sans, but with the way he says it, it doesn't. "like papyrus told you. and you're this weird little squishy whatsit who doesn't give a shit about anyone but yourself. you like seeing people in pain, it's hilarious to you. and you. you live inside monsters' bodies. find ones that aren't too strong, take 'em over, reshape them in your preferred image, and wear them around until they break down. you got magic. pretty powerful, too. but just when you're inside someone."
"Okay?" Undyne wasn't expecting Sans to suggest role playing but sure, why not? Also, that sounds a little dirty. Whatever.
"you jump into the underground. some other version of the underground... that part's bullshitty, forget it. you're 'here'. because you wanna grab someone. like. me."
"This alien thing IS dead already, right? 'Cause if not..." Undyne leans back in her seat, fingers flexing. She always considered humans to be the enemy of monsterkind, but this creature Sans is describing is somehow worse. And, from the sound of it, a lot easier to destroy with a single energy spear.
"uh. very. according to 'me'. anyway, so... now you're me except way tougher. think, like... what papyrus can do, except more colorful, and... wh-whatever, not relevant. just, tougher. as, like, as a percentage, or something... what's the probability that you kill anyone before you leave?"
Undyne's response is instantaneous. "Low. Math is for losers, but low."
"...why?"
She's loud and strong but she's not dumb, and she's well aware of what's being asked here. But Sans expressed this as a hypothetical so that's the language she sticks with. "If 'I' were some asshole mind-controller who goes after weak monsters because they're easy targets, then 'I' would have to be a COMPLETE coward. And cowards don't put themselves in danger on purpose."
"what if you got caught in the act?"
"That's possible." Undyne leans her chin on her hand, eyebrows knitting together she sips her tea. "But if 'I've' been doing evil crap long enough to have an M.O., then 'I' know what I'm doing. I'm the one who picked the time and place, I'll know how to avoid anybody who might cause problems for me."
Sans takes a sip. He was always kind of meh about tea, but it's warm.
"You think it killed someone?" Undyne asks.
Hearing Undyne speak about it so straightforwardly... he doesn't like it, he's the one who brought this topic up but he doesn't like it. "i don't know. that thing was twisted. mostly it just... goofed around, but it it had no problem with hurting people. if it were just self-defense, i could understand... that happened sometimes, but i don't know if it also... it might've hurt people back home. i don't have exp but i already 'should' now and don't, so... i don't know. can't remember. but that thing liked people being miserable."
Undyne mulls this over. It all sounds like a weird anime plot, this story about clones from alternate dimensions, but she's talking to one right now, and it's all real to him. At least the mind-control part is believable, she knows humans are capable of that, too. "Okay. Yeah. It makes sense that you would be worried. Whatever that thing did, it wasn't you, so it wasn't your fault. But of course you're worried." If anything, she thinks, this all reflects badly on the other Undyne for failing to protect him. "Why do you actually think it hurt people back home, though?"
"told you it's a sadist. was."
"Did it talk to you?"
"k...kinda. sometimes. after a while, i stopped... i dunno."
"And it liked making you unhappy."
"yeah." With a parasite continually feeding on his SOUL, unhappy would be a mild description of his baseline state of existence, but the less said about all that, the better.
"Did it ever tell you that it hurt your friends?"
"if it did, i don't remember."
Undyne leans forward on her elbow. "Then it definitely didn't touch them. Torturing somebody by bragging about hurting their friends... making sure they know exactly what it did, and can't ever forget it... that's CLASSIC bad guy technique! Why wouldn't it use that strategy, unless it really DIDN'T do anything, and didn't think it could get away with lying? Come on!"
Sans tries to think of a counter-argument, but nothing much comes to mind. It has less to do with Undyne's reasoning and more to do with his own exhaustion, probably, but his silence sends a certain message.
"How long have you been worrying about this?" she asks.
Sans looks away. He's spoken more in this one sitting than he has ever since he was freed, and it feels sort of good, in a way, but risky, too. Like he's exposed too much. "don't tell papyrus. not that it's—i'm not dangerous now. i swear. just don't want him to have to worry about it."
"Uh... sure, I guess." It wouldn't be the first time she's kept something from Papyrus for the sake of not upsetting him, though she has a feeling Papyrus is already seriously worried about this guy either way. "Have you told, uh, the other Sans any of this?"
"nah."
"Are you—"
"nah."
"Well... whatever. It's good that you came here to talk about it instead of just not telling anyone."
"...thanks?"
Undyne finishes her tea. As wild as his story may be, this guy just sounds so dejected, so unlike the cheerful weirdo she knows and... tolerates. It makes her want to punch somebody on his behalf. "I guess you already have a lot of people asking if you're okay all the time, right?"
Sans yawns and rests his head on one arm, his other hand wrapped loosely around his half-full teacup. "kinda."
"I won't, then," Undyne says. "But... if you're ever not... you can come back here again whenever you wanna hang out, or whatever."
"ok."
"You want more tea?"
When Sans nods, Undyne leans over to grab his cup. As she turns back to the stove, he tries to think of a new topic. Looking out across the room, his focus lands on the piano by the window.
"hey, undyne... can you teach me how to play the piano sometime?" he asks. "if you're down, i guess."
"Uh... yeah, sure, why the hell not?"
"hey. what's the difference between a piano and a fi—"
"Oh my GOD never mind I'm gonna kill you. Throw you in the pond out front."
"heh heh heh."
A minute later, when a still-grumbling Undyne goes to hand over his teacup, she realizes Sans is already asleep, head resting on the table. She could just poke him awake, but she gets the feeling he could use the rest. After some sleepy consideration, she slings him over her shoulder like a little sack of potatoes and goes back to her room to dig around for the foldable cot she keeps for when Alphys stays over. She knows that thing is somewhere around here...
It's not a cure, or a fix, or anything. Sans isn't even super interested in music (annoying his brother with incidental trombone music back home doesn't count), and he forgets to practice more often than not—and not forgetting as in being his typical lazy self and knowingly letting the keyboard get buried under dirty laundry, but genuinely forgetting, which is unsettling. He still went for the first lesson, just to see what it would be like, and he went again the next week because Undyne didn't seem to expect that he would, and because it made Papyrus so happy to see him showing interest in something new, and naturally Papyrus also liked having an excuse to pester his original brother for failing to follow that example. By the third week, it feels like a thing, and Papyrus helped him dig up a keyboard to mess around with, so he figures he might as well keep going.
As creepy as it sounds, the attention from Undyne is what has him hooked. It feels so good to interact with another monster, he went to that first lesson and she was watching him, correcting his posture and then slapping him on the shoulder a little too hard for getting a simple song right, and he almost had some kind of meltdown right there in her living room because it felt so good. And she throws herself so completely into everything she does, whether it's defending the Underground or reminding some boneheaded dumbass about correct hand placement for the eight billionth time, she's technically a near-stranger but she's still her, she would fight to protect him if she had to, whether from a human or another parasite or anything else, and that means fuck-all in the face of the universe-eating cosmic horrors that he now knows to exist, but he doesn't even care. He exists. He's noticed. He's himself. If this world flies off the rails tomorrow, he won't die as a puppet.
(Being able to hear people drop F-bombs is also nice. He was a little too busy wishing for death to care that the thing wearing his body and feasting on his SOUL also happened to be freakishly puritanical to the point of magically censoring everyone in its vicinity, but he figures he may as well appreciate the little things. Fuuuuuck. Wonderful.)
Sans is walking back to the Riverperson's dock with a backpack slung over one shoulder and his fingers tapping out the melody to a song he'd been learning when he feels a slight vibration in the ground through the soles of his borrowed sneakers. He's being followed.
Running away is for cowards, smart people, and athletes, so he stops walking.
"'sup, flowey."
He waits.
He doesn't see the vine shoot out to grab his ankle, and his reflexes are so shot that he'd have no chance of avoiding it even if he tried. He's standing and then he isn't, and only luck allows him to catch himself with his hands before his skull would've cracked against the floor. The world skids sideways and then he's dangling upside down like an animal in one of those rope snares like you see in cartoons. His bag is somewhere on the ground below him, a couple pages of sheet music scattered around it.
From upside-down, Flowey glares with his tiny baby face. "What are you doing here?" he demands.
"hanging out."
"Don't try to be funny, because you aren't." The little flower rolls his eyes. "What are you doing here?"
"i WAS walking home."
"This isn't your home."
"that's where the 'walking' part comes in."
Once upon a time, Sans might have been worried, might have been preparing himself for a fight. Since then, he's met world-eating abominations and things that looked like humans but weren't and a version of himself that was actually a tentacle creature made of black goopy stuff who fed on pure despair and drank baby kitten tears (or something like that, whatever, Sans was a little distracted at the time), plus the starfish whatsit that lived in his skull while indulging its weird fetish for short skeleton monsters with bad hygiene. Being menaced by a territorial feral child with a god complex feels quaint in comparison, like the ass-backwards nostalgia of kid's medicine that allegedly tastes like bubblegum.
No, that isn't true. The feeling of constriction around his ankle is actually kind of unbearable, it's too much like—that—but if he lets his discomfort show then Flowey will capitalize on that weakness. Not that Sans is a pillar of strength anyway. He's rattling even more than usual.
"What kind of messed up game have you been playing? The Underground is MINE."
"ok."
"'Ok'?"
"yeah."
"That's it?"
"this place isn't mine, so. yeah."
Sans wonders what the chances are of somebody showing up and rescuing him. Low, probably. Is he going to die like this? Really?
"Papyrus told me how you 'appeared' one day... how did you get here? What do you want?"
"to go home. we've already been over this."
The vine loosens. Sans lands in a heap and lies where he fell, outwardly trembling and inwardly resigned to some more verbal abuse before he gets rescued, killed and then probably brought back without knowing it, or tossed aside like a broken toy. Flowey glares, poised to retaliate at the first hint of aggression, but Sans gives him nothing and he's not sure what to make of that. It would seem like Sans is just trying to play it cool, as he usually does, but he also usually would've dodged the vines. The Sans who Flowey knows always dodges, and he isn't any kind of extradimensional universe-hopper. As far as Flowey knows. Not in the way this one allegedly is.
Flowey leans closer, about to hiss something, then freezes. Papyrus has told him plenty of interesting bits and pieces about 'Sans the Sequel', but he didn't mention everything, and Flowey can only ask so many questions before it gets suspicious. Sans has one darkened eye socket, and in the other glows a near-broken SOUL.
"Wh-what's wrong with your eye?! What happened to it?" Flowey blurts out, forgetting all about trying to be intimidating.
"ran with scissors."
"Are you dying? Is that your SOUL?" Flowey is intimately acquainted with what dying monsters looks like, and he's never seen Sans looking anything like this. Not while also being capable of walking around and talking like nothing is wrong, anyway.
"if i kick the bucket, you're the first person i'll inform."
Flowey is too distracted to be annoyed. Mostly. "That's NOT normal. It shouldn't look like that."
"yeah, that was pretty much alphys' diagnosis."
The vine retracts, flicking like a hand trying to rid itself of cooties, and then disappears into the ground.
"...Give me a real answer, are you dying?"
"i dunno. maybe."
When Flowey neither physically nor verbally lashes out again, Sans sits up. His borrowed clothes are dirty and damp now, but they were already like that anyway.
"hey, flowey..."
"What?"
Sans thinks about posing the same question to him that he did to Undyne. She gave a heroine's opinion and Flowey can offer the closest thing to the sadistic parasite's own perspective as Sans hopes to ever have, since the thing is dead and damn well better stay dead. Except Flowey is Flowey so maybe Sans shouldn't put any more murdery ideas into the mind of a time-traveling and volatile kid's head. There's plenty already floating around in there.
Changing course, he lets out a sigh. "i might seem to you like an enigma, or something, but i'm... really not. honestly, i'm the least interesting 'me' you could ever meet. so, can i just go now? i'm not a threat to you. just wanna go home. i'm tired."
When you've heard one monster plead, you've heard them all, and begging for mercy hasn't worked on Flowey ever since the monotony of his own existence drove him to start breaking his toys. Sans isn't pleading, though. He barely seems to care, not just as part of his normal careless attitude but for real, and that isn't how this game goes—Flowey pretends to be friendly or else jumps straight to hostility and Sans deflects everything with his stupid unfunny jokes, and then they play cat and mouse and eventually fight and Flowey usually loses because Sans cheats. But Sans isn't playing along.
"You were never a threat to me, ANYWAY," Flowey tries, but his heart isn't quite in it, and not just because he's literally heartless.
"yeah, i know."
Silence pervades. Flowey isn't gullible enough to take Sans at his word about being harmless, but he isn't sure what to do. Shake Sans around some more until he reacts? That cracked SOUL disturbs Flowey, and Sans is constantly trembling like he might disintegrate if you so much as look at him too hard. Is it too late to play friendly and see what responses he can get that way?
They stare each other down, listening to the dripping of water from the cavern wall and the faint rattling of bones; Sans almost starts laughing at the baffled look on the little brat's face. He picks himself up and slowly collects all his dropped sheet music. Flowey lets him go.