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The CORE buzzed with that low, omnipresent hum — too steady, too loud, like it was trying to drown out something.
Gaster stood at the console, gloved hands moving over switches and levers, each one shutting down a section of code, dismantling pieces of his past one flick at a time. The blue glow of the screen lit up underneath his eye sockets like bruises.
“y’know, if i didn’t know better, i’d think you were cleaning up after a murder.”
Gaster flinched.
He didn’t turn around. “I thought I told you to stop sneaking up on me.”
“you did.” A pause. “still funny, though.”
Sans stepped into view, arms folded, hoodie slouched, grin lazy — but there was something tight in his jaw. Something watching.
Gaster returned to the controls.
“no clipboard today?” Sans asked, squinting around. “no logs? no weird scribbles about soul resonance and probable reaction to isolation-induced trauma?”
His grin sharpened. “we takin’ a more casual approach to guilt now?”
Gaster’s hands froze for a beat.
“…I’m shutting it down,” he said. “The lab. All of it. There’s no reason for it to exist anymore. The only remaining purpose for the CORE is to power the underground and, well, now that we’ve reached the surface..” he trails off.
“huh,” Sans said. “and what brought this on? morality? regret? or did you just figure out the paperwork’s too much of a pain when everyone you experimented on’s still alive?”
He didn’t expect an answer — and didn’t get one. Just silence and the sharp hiss of depressurizing valves.
Then, “He cried.”
Gaster’s voice was quiet. Rougher than usual.
Sans blinked.
“Papyrus,” Gaster continued. “When I hugged him. He cried.”
Sans’s grin dropped, just slightly. His shoulders stiffened, but he didn’t look away.
“and what, you want a medal?”
“No,” Gaster said. “I want to understand why he still trusts me.”
Now Sans laughed — short, bitter.
“kid’s got a big heart. too big. you don’t deserve it.”
Gaster didn’t argue.
They stood in silence. Steam hissed from a pipe in the wall. Data flickered across the screen like static memories.
“…you’re not messing with him, are you?” Sans asked suddenly. Tone flat now. Serious.
Gaster looked up.
“because if you are—if this is some new angle, some twisted experiment where you figure out how much forgiveness you can squeeze outta a kid who just wants to believe you’re not a monster…”
Gaster turned fully to face him.
“I’m not,” he said.
Sans stared at him. Didn’t blink.
“You sure?” he asked, voice low. “’cause you’ve been pretty good at pretending you care about your test subjects when it gets you results.”
The room went colder.
Gaster’s expression didn’t change. But his hands were shaking — just slightly, almost imperceptibly.
“I’m not pretending,” he said. Then, after a beat, “I just don’t know what to do with the parts of me that… care.”
The confession hung in the air like a skipped beat in a song.
Sans tilted his head, unreadable. “sounds like a you problem.”
Gaster gave the smallest of smiles. Bitter. Soft.
“Perhaps.”
Another silence. This one… less sharp.
Then Sans exhaled. Rubbed the back of his neck.
“…i’m watchin’ you, old man.”
“I wouldn’t expect anything less.”
And for once, it didn’t sound like a threat.
It sounded like trust. Almost.