1) Sans losing control of his powers when Toriel kisses him - at least the first time. Nothing drastic, but he might send his mug or pie shooting across the room, or literally float off the ground in a daze. A tiny Gaster skull appears and its mouth sags open as it gently drifts to the ground with hearts in its eyes.
Does Toriel know about his power levels? She might now.
2) Has anyone ever seen anything where someone pretends to be a sniper to get someone to do something but in reality it’s just a person with a laser pointer? -- Gallifreya
Frisk had been hiding, very effectively, to peek in on their Mama Toriel and Dunkle Sans getting cozy after bedtime. It wasn't really breaking the rules. It was holiday time. Kids were allowed to stay up on holidays. Besides, they really wanted to know that Mama Toriel and Dunkle Sans were okay.
They weren't like regular parents. Even for monster couples. For a start, they weren't really living in the same house.
Sans spend every other night 'sleeping over' with Mama Toriel. Possibly because he was too lazy to go home until the following day. And when they were together, he and Mama Toriel barely did more than holding hands. Or one arm slung negligently across the other's shoulders. Most often Mama Toriel's arm across Dunkle Sans' shoulders. Chiefly because she was gigantic and he was barely taller than Frisk.
They would watch television, and Sans would fall asleep leaning against Toriel's softness. And though they did seem content... there should have been more.
Frisk had been watching other kids' parents for weeks in barely-contained jealousy. Saw how moms and dads would casually hug, kiss, or otherwise show affection in a multitude of ways. Sure, Mama Toriel and Dunkle Sans would make each other laugh. Happiness was good.
Maybe it was because all the mom-dad couples, and the mom-mom couples, and the dad-dad couples... had all met before they got kids. There was that one kid in Frisk's class who only had a dad... and a rapid succession of 'aunties' that never lasted longer than three months. And a mom they got to see once a week because of legal issues.
Frisk didn't want things to be that sad, ever. Which is why they were watching in the first place.
Dunkle Sans snuggled up close against Mama Toriel as they sat together on the couch. Her arm was already around him. It didn't matter what they were watching, they always snuggled like that. But tonight, it involved romance.
And tonight - Mama Toriel leaned down to lay a good smooch on Dunkle Sans' whitened skull.
Frisk could see him startle despite the fact that their hiding place obscured everything but the top of his head. Blue magic flared, sending everything small around him to the nearest flat surface, including the ceiling.
Giant, dog-like skulls from Frisk's worst nightmares appeared out of nowhere, but did not blast white death at anything. They jut kind of... lolled. And panted. But that didn't stop Frisk from shrieking in abbreviated alarm.
Sans must have reacted on instinct, whipping Frisk from their hiding place to join the dance of things around himself and Mama Toriel.
"Oh. It's just you. Ain't you up past your bed-time, kiddo?"
The dog skulls greeted Frisk like an old friend. Fawning and licking them with invisible tongues.
Frisk risked a cautious pat. They were like ghostly, headless dogs. And actually fun.
Sans' cheekbones were vivid red. He regained slow control and put most of everything back into its place. And Frisk down on the rug. "Sorry about that," he murmured. "I kind'a... um..."
"Was not expecting much?" prompted Mama Toriel. She smooched him on his reddened cheekbone and was rewarded with enhanced blushing.
"Y-y-y-yeah," he was trembling. The bright points of his eyes had gone out and he was sweating. "You mean it?"
"Of course I mean it, my love."
Somewhere, an invisible status bar was maxing out. Frisk giggled, watching Sans' face turn red, followed by the rest of his visible bones.
"...how'm I gonna break it to pap...?" he squeaked.
"I think your brother has someone else to read to him, anyway," cooed Mama Toriel.
Frisk grinned even wider. They knew who that was. And they knew how Uncle Pap seemed to walk on air that every other night that Dunkle Sans 'slept over'. Now there was very little to stop him reaching his dream of bathing in a shower of kisses on a regular basis.
And nothing stopping Sans, either.
He had to stand on the couch seat in order to nuzzle his bony face into Mama Toriel's neck fur. Something that made her blush in turn.
There was going to be a happily ever after!
"I said chant!" shouted the sports coach. Mister Sergeant. "That means no flapping hands! We all use our voices!"
Frisk, already near to tears from the shouting, hid their face and broke from the marching lines of kids in the PE class to crouch near the ground.
Which was exactly the wrong thing to do, according to Mister Sergeant. "YOU ARE MOVING YOUR PASTY ASS, KIDDO, OR YOU ARE GOING STRAIGHT TO DETENTION! HUP HUP HUP HUP HUP!" The whistle made Frisk flinch.
"Hey yo. Teach. Quiet word?"
Frisk risked a peek. Dunkle Sans! He hadn't been there a second ago, but now... He had ways of just... getting places, somehow. And a knack for turning up just when all seemed hopeless.
People like Mister Sergeant were why Frisk ran away to Mount Ebott in the first place.
"Listen, sir. I know Frisk is your kid and they get some degree of special attention, but you have no authority to tell me how I run my class. I'm trying to instil these jelly doughnuts with a sense of self-pride and fortitude. I went through military-style training as a kid and I turned out just fine."
"And yet you think it's all right to scream at a scared kid and blow a whistle in their ear," said Sans. "And you're right. I have no authority whatsoever to tell you how to do your job." His eye gleamed blue. "But I can tell you that you got something on your shirt."
Mister Sergeant looked down. "It's illegal to threaten people, up on the surface, pal. I could throw you in jail."
"Who's threatening?" said Sans. "You've managed to tick off every parent in this school with your teaching regime. And I'm not the one in charge of the laser sight. I'm just trying to convince you that there's other ways to do things. Friendlier ways."
"With a sniper on your leash?"
"Do you see any way I could talk to a sniper, pal?"
Mister Sergeant had to growl, "No."
"Then I ain't got no sniper. Just ease off on the yelling for a week. See what it does for you. And -ah- try encouraging the kids instead of the whistle."
Mister Sergeant mumbled, "Sure. Whatever," and Frisk could see three red dots of light on his chest. A fourth blinked on as he spoke.
Frisk would learn, much later on, that it was Undyne, Mettaton, and Alphys on top of one of the school roofs with laser pointers and no weapons at all. It was a co-ordinated semi-prank that made Mama Toriel sigh with exasperation.
But it did make Mister Sergeant a kinder and gentler teacher. And for that, Frisk was glad.