From the Fire
Grillby was a very kind monster, once someone got to know him passed his hot-headed exterior. And with a pun like that, it only made sense that Sans had been the first one to talk to him.
Grillby didn't talk back, but he appreciated the effort.
It went back and forth like that, Sans talking and never paying his bill, Grillby changing his flames according to his approval or disapproval, or to simply show that he was listening. That was how it went. Until one day, Sans was his only customer.
It happened some days, everyone else at a party, or working, or doing something. He didn't always have a large crowd, but no matter what, Sans was there at least once a day.
Nighttime shined through the window, as Sans sat at the bar and Grillby cleaned a glass. The customer glanced at the bartender, studying him, before mumbling into his fry and taking a bite. Grillby turned his head, curious about the look he got.
"it's nothing, grillz." Sans assured him, but he wasn't convinced. His flames formed a question mark above his head. "i'm just wondering something about you. you don't, uh, look like the other flame-monsters. your color, your lack of speaking..."
"I can speak, Sans." His voice was warm, a bit higher than one would expect, but still comforting.
"still, color, and not related to the other fires..."
"You want to know where I came from." It wasn't a question.
"yeah, well, i've told you my story. it was boring, but it was mine."
Silence, before a small question.
"You... Worked with the Scientist before Alphys?" He wasn't used to speaking so much, he stressed some wrong syllables and worded some parts wrong. Sans tensed, not expecting anyone else to remember Gaster, but gave a nod.
"The... There were two... humans. King Asgore never got the SOUL of."
"I cannot let you go further." He said, moving his hands as he spoke. The boy tightened his grip on the pan, raising it to defend himself. He didn't want to fight the skeleton, but...
He had to get his sister home.
They had both been curious about the mountain that three kids had already fallen down, only to never to be seen again. It was exactly that story that got the ten year old and the six year old to climb the mountain. The older brother was wearing an apron and holding a cooking pan, since the two of them had decided to go right after playing dress up. They had made it to the top, and peered down into the hole. There didn't seem to be a bottom.
His red hair moved in the non-existent breeze, and he felt his soul be pulled into battle. The scientist... He attacked from the left and right, and the human blocked his attacks with his sister's pan. This wasn't so ha-
An attack from the front. He stumbled back slightly, but he was still alive. His sister grabbed the back of his shirt, letting out a small whimper.
"Please, just let us leave!" It didn't seem like talking was helping. Another set of attacks, left right left top left top right right right top FRONT-
Moved back, again. He felt the heat on his back. His sister gripped his shirt, closer to falling in than he was. He had to protect her.
He attacked back.
But it hardly did any damage, and another set of attacks came from the scientist. Front left right front back left left right left front front front left front right right right fr-
He took a step back, and heard a scream from his sister. Every action afterward happened quick. The redheaded boy turned quickly, throwing his sister to the floor of the CORE, and he had his feet balancing on the edge.
His sister was stumbling, trying to catch her footing, but the scientist had moved forward and grabbed her. A small blaster, and- the crack of her green soul echoed through the CORE.
The scientist- no, the monster -took another step, and another, heading toward the boy. It grabbed onto the apron of the child, preparing its blaster again, but no. He wouldn't let anyone get his SOUL.
Using the entire weight of his body, the human grabbed the monster, and flung the both of them over the edge. The apron was ripped off and fluttered down to the floor where human and monster once stood.
The scientist's white soul escaped from the dust of what was once its body, and the human reached for it. It wouldn't help, much. He would get a bit stronger, but he couldn't fight flames. They burned. As he closed his eyes, gritting his teeth and trying to not cry at the pain, a light blinded him.
A small green SOUL shined brightly on the floor above him, a bit away from him. His mind was racing. A human couldn't take a human's SOUL, but if a monster soul took a human's SOUL-
He had to try it. He had to live, and have his sister live on alongside him.
He reached for the white soul.
Sans was quiet. Grillby thought that the skeleton might try to attack him, after learning that he was the reason Gaster fell into the CORE. He was the reason that the scientist died at the hands of his creation. But he stayed silent, eating the last of his food. The two lapsed into silence, Grillby cleaning the last glass spotless and Sans finishing up.
They never spoke of the story that night, nor any nights after. But they talked about Gaster, on occasion, the only two to remember him. They talked about how Sans never noticed that Grillby's glasses were Gaster's, taken to adopt a persona. They talked about Sans' work with him, and Grillby understood all of it, remembering the feelings and emotions of the monster through the soul he had taken.
They talked, they reminisced, and they became closer as 'friends.' Grillby didn't mention the giant tab that Sans had in exchange for the skeleton ensuring that no human tried to fight the fire monster, to make sure that no one saw the deformed SOul of what used to be two children and a scientist.