Sans lurked across the road from the town library, listening to the sound of raindrops tapping on his skull. His clothes were getting wet, letting a chill creep deep into his bones, but he didn't care. It didn't matter.
He kept his eye sockets on the library's front door. Sooner or later, Frisk would come out that door. Sans hadn't decided what he'd do then. Could be fun to sneak up on them. Or, could be fun to let them see him, then disappear, make them think they were stuck in the rain after all.
It was Saturday, and on Saturday afternoons Frisk had their library thing. Toriel had explained it to Sans once or twice: Something something other neighborhood kids, something something snack time, story time, time to play Pokemon cards or whatever, something something good opportunity for Frisk to socialize like a normal kid without their mom looking over their shoulder. Sans didn't see the point. Sure, maybe Frisk could stand to make more friends their age, and, sure, going to school where their mom was the teacher probably made that hard, but this was Frisk. Frisk didn't need to socialize like a normal kid. Frisk wasn't a normal kid. That wasn't bad, it was why monsters lived on the surface again.
But whatever. Frisk claimed to enjoy it, and it made Tori happy, so off they went, every week, for a few hours away from the rest of the household. They always walked to and from the library alone; it wasn't far and this was a monster-heavy neighborhood, so even Toriel wasn't afraid of anything happening to them.
Too bad the neighborhood couldn't account for the weather.
The forecast for today had been partly sunny with a fifty percent chance of precipitation, practically daring optimists to chance it. Frisk had responded predictably: Off to the library with no umbrella, no boots, and no raincoat. Of course it was raining by the time their thing was over. At least the sun was still out. Even so, Toriel asked Sans if he could use his "shortcuts" to pick Frisk up so they wouldn't have to walk in the rain. If it'd been anyone else he'd have said no, but, well… Best not to rock the boat with the new roomie, right?
The library door opened and Frisk stepped out. As Sans watched, they stood there a moment, head tilted back as if to make extra sure that yep, it was raining. Then they shrugged, turned, and started down the sidewalk. If they'd noticed Sans waiting for them, they didn't show it.
Sneaky time it was, then.
A second later, Sans was on the sidewalk next to Frisk, just far enough behind them to stay out of their peripheral vision.
"Hey, kid."
Frisk jumped at his voice. Sans snorted. Wasn't often he caught them by surprise. Nice to know it could be done. They soon recovered and resumed walking, though. Sans shrugged and fell into step beside them.
"Thought the walk home might dampen your spirits today."
Frisk rolled their eyes, but Sans spotted the ghost of a smile haunting their lips.
"Wanna take a shortcut?" he asked.
They shook their head.
"No? Seriously? You're gonna get soaked out here."
They shrugged.
"Tori's scared you'll 'catch your death,' y'know. Her words, not mine."
Frisk smirked.
"Have a little faith," they said, "You've known me for months and haven't seen me die once, right?"
"Heh. You got me there."
Sans slipped out of his damp jacket while Frisk amiably kicked through a series of puddles. Holding it out to them, he said, "Here, at least put this on to keep some of the rain off. Then maybe Tori'll only kill me a little when we get home."
Frisk laughed and accepted the jacket. Halfway through putting it on, though, they froze, eyes wide with shock.
Sans stopped and looked back at them curiously.
"What's that look?" he asked, "Something wrong?"
"…it's warm."
"Huh?"
Frisk blinked at him owlishly as they settled into the jacket and fumbled with the zipper, offering no further commentary.
"…uh, duh, it's warm. Do I look dead to you?"
Frisk didn't answer that. Instead, they said, "I guess I thought skeletons were cold." They zipped up the jacket and resumed their journey down the sidewalk, anxious to get back to their puddle-stompin.'
"Well, we're made of mostly magic, same as any monster. Magic's hot, y'know, especially raw. Why do you think Tori uses it to cook?"
Frisk looked thoughtful at this. Sans tried not to laugh. His jacket was big enough to hang down to their knees. With that expression, they looked like a miniature monk in a tiny blue robe, contemplating life's deepest mysteries as they searched for their hands in the depths of the over-long sleeves.
They hadn't bothered to put the hood of the jacket up, so Sans flipped it up for them, then playfully tugged the edge of the hood down past their eyes.
"Hey!" they squealed, giggling and blindly flailing their arms in an attempt to knock his hand away. The sleeve situation grew all the more grievously flappy. Sans chuckled and, after a few more seconds of watching their flappy distress, readjusted the hood so Frisk could see again. They stuck their tongue out at him before beginning anew the search for their own hands.
As the two of them continued their walk, he asked, "Wait, how is this news to you? You tellin' me you've never hugged Papyrus?" Unthinkable.
"I tried once, but he said his hugs were so 'powerful' he was afraid I'd get hurt."
Sans laughed.
"He does really go for it, but hey, he hasn't killed me yet, so you should be good."
"I'll remember that." In Frisk's tone was a promise ineffable as ancient prophecy. Sans smirked. Someone was determined.
Almost home now: Once they crossed the river it'd be a short walk up the street, and they were already halfway across the bridge. The water rushing underneath was a soothing noise, a soft, ambient harmony to the raindrops' melody. Sans enjoyed the sound so much he made it all the way across the bridge before noticing Frisk wasn't beside him anymore. He looked back.
Frisk had stopped in the middle and turned to stare out over the river, leaning on the railing.
"C'mon. Bad enough you're gonna come home sopping wet. You wanna come home late too?"
Instead of answering him, Frisk pointed.
Sans looked where they pointed and saw—shoulda guessed—a pale rainbow, low on the horizon, stretched across the river.
"Huh. Good catch." Sans ambled back to join them.
The two of them stood there a while, and the rain began to let up, becoming one of those faded rains that was more like an overzealous fog. The rainbow began to waver and fade as well. Too bad. It was real pretty. Funny how they would've completely missed it if they'd taken a shortcut, or walked a little faster or slower, or if Frisk hadn't glanced that way while crossing the bridge. Convenient how it all lined up. Couldn't've planned it better…
"Did you know this would be here?"
Frisk's back stiffened. Any other kid would've found that a weird question, but this one looked guilty.
"No," they said. They didn't say anything else. A damp silence stretched out between them, long enough to get uncomfortable.
"Welp," said Sans at last, "We should really be gettin' home."
Frisk nodded and turned to him. Then they blinked and snorted, one hand flying to their mouth.
"What?" Sans glanced down at himself. "Oh."
The rain had thoroughly soaked his white T-shirt, and now it clung to his ribs. He crossed his arms over his chest indignantly.
"Now I get why you didn't wanna take a shortcut, you little perv."
Frisk snorted again.
"I should've brought an umbrella today," they said apologetically.
"Don't worry 'bout it. C'mon." Without really thinking, Sans grabbed Frisk's hand to lead them across the bridge. They fell into step beside him, but, weirdly, jerked their hand away.
"Hey!" said Sans, pretending to be offended. Well, mostly pretending. Well, whatever, right? Yanking them around by the arm was Tori's deal, not his. He didn't have to care. It didn't matter.
"Sorry," Frisk said, "Your hands are cold."
"Guess magic only gets ya so far. Sorry, buddy."
Frisk murmured something too quiet for Sans to hear.
"Huh?"
"Cold hands, warm heart."
"You know I don't have a—"
"Yeah."
Suddenly Frisk was holding his hand again. Tight, as if to make up for letting go.
"Heh, okay." Must be a human expression. Funny, Frisk didn't use a lot of human-specific language, especially around monsters. Not that they were all that talkative in the first place, to be fair.
Actually, that wasn't fair. They weren't that quiet. Sans just thought of them as a quiet kid because they'd never said much the day he first met them. The same reason he thought of them as unflappable even though in the last ten minutes alone he'd surprised them thrice: The sudden greeting, the warm jacket, the cold hand… Throw in the unexpected rainbow and that was four times (Quice?) they'd gotten surprised, all in a row. Probably there were even more little things he didn't think to count. Not like it was normal to keep track of this stuff. Not like he needed to keep an eye socket out for anomalies anymore…
It really wasn't fair to the kid, how months later he still mostly thought of them in terms of the day they met, but he couldn't help it. It'd been a big day, after all. And it was true: On that day, nothing seemed to surprise them. Not the whoopee cushion in his hand when he first greeted them or the one on their seat at Grillby's when he took them to lunch. Not the hotdog he put on their head. Not…
You know what would have happened if she hadn't said anything?
Buddy.
You'd be dead where you stand.
Hey, lighten up, bucko! I'm just joking with you.
They hadn't found that funny (unlike the whoopee cushions and hotdogs) but they hadn't seemed shocked either. They watched a talking flower damn near kill all their friends and barely blinked. Even at the craziest moments, they'd always seemed to know what to expect, what to do, what dumb thing squirreled away in their pockets would help.
But now you couldn't bet on them grabbing an umbrella if it was gonna rain.
Sans grinned and squeezed Frisk's hand.
"Wait a minute," he said with exaggerated suspicion, "Are humans warm?" He let go of their hand. "I dunno if I can deal with this. Too freaky."
At first their face fell, but then it rearranged itself into a pout.
"You're messing with me."
"Apparently I'm not doing a good job."
"Don't close the hotdog stand."
"Someone's wearing their sassypants today."
They giggled.
"You know who would freak out for real, though? Papyrus. Make sure to hug him nice and tight next time you see him."
Frisk glanced up at Sans curiously, almost tripping over their feet as they peered past the edge of the hood.
"What?" said Sans.
"Papyrus is scared to hug me 'cause I might get hurt, but what's your excuse?"
The question caught Sans off-guard. For a second there he couldn't believe he'd never hugged the kid, but, if he had, his warm jacket wouldn't've caught them off-guard, so…
"I dunno. Guess I'm not a hugger."
They'd reached their driveway now and begun the trudge to the front door, Frisk's socks audibly squishing inside their muddy shoes. They'd just hit the porch when the door flew open to reveal a very stern Toriel.
"Sans. I believe I made it clear you were to retrieve Frisk so they wouldn't have to walk in the rain, did I not?"
"Yeah." Sans scratched the back of his skull sheepishly. "But they didn't wanna take a shortcut, so…"
Frisk nodded their confirmation. Toriel sighed and shook her head.
"Take off your shoes before you come inside, both of you."
"Guess that's what we get," said Sans, glancing sideways at Frisk, "We didn't listen to her, and now our soles gotta suffer for it."
Frisk was unimpressed—Too much of a stretch?—but Toriel laughed the same way she always did: Loud and honest. When she finished laughing she said, "That's enough ribbing from you, mister."
Frisk facepalmed while Sans snickered.
"I'll start some tea for you two." Toriel disappeared into the house. She didn't sound stern anymore; clearly it didn't take much for Sans to get back in her good graces. As he shuffled out of his sneakers—not bothering to untie them—he felt eyes on him and looked down to see Frisk staring up at him. Once they'd noticed him noticing, their gaze slid away and they bent to untie their shoes. Were they still thinking about the whole hugging thing? Or maybe still sore over the rainbow accusation? Or maybe they were fine, and he was just being paranoid. Usually he could read that face like a book, but sometimes he got too far inside his own head to latch onto what the kid was thinking.
Sans sighed as they stepped into the house.
He wondered if it was gonna be this way forever. If no matter how much time he spent with Frisk in "normal kid" mode he'd never look at them without seeing the sweet—but eerily quiet—human who walked through Hell looking like they'd seen it all before. He wondered if he'd ever forget the look on their face during dinner at Mettaton's stupid restaurant. I mean, look at yourself. You haven't died a single time.
He wondered if the word "anomaly" would ever stop echoing around his skull whenever he saw them.
He'd thought about this stuff before, but, thinking of the look on Frisk's face just now, he wondered something new: What echoed around their skull when they saw him? If he had to bet, he'd put his money on the whole "dead where you stand" bit.
It occurred to him that he'd never hugged Frisk, but Frisk had never hugged him either.
"Hey. Kid."
Frisk—who was wiggling out of Sans's jacket partway down the hall—turned and tilted their head at him questioningly.
Sans spread his arms wide—jeez, this felt awkward—and smiled.
"C'mere."
It took them a couple seconds to figure out what he meant. Nice to know it didn't take much to surprise them. Real nice.
When they figured it out, they hesitated a second—like they thought it might be some kind of trick—but then they grinned and scampered back up the hall, all but crashing into him and wrapping their arms tight around his waist. His jacket laid forgotten on the floor.
"Oof, love you too, kid," said Sans, chuckling and squeezing them back.
Maybe the echoes in his skull got fainter after that. Or maybe they just didn't matter.