I made a one shot based on a "What if" idea... like What if after so many Genocide runs, you face off against W.D. Gaster and lose? Well here's the idea, feel free to come up with ideas to continue off of it because I for sure won't... just getting the idea out there.
Sans's vision was beginning to fade as the red liquid dripped from the wound that the kid... no the hell spawn made. Through blurred vision Sans saw someone standing behind the kid, what he could make out was a tall figure and a skeletal like head.
"papyrus..." that was the first clear thought that came to mind. He felt the figure's gaze on him. Sans swore through darkening vision that "Papyrus" was smiling sadly at him. That was enough to convince Sans that it was his brother as he weakly walked past the kid, who had flinched a little till he was well past the kid.
"you want anything...?" Sans asked, feeling his hold on his own life beginning to fade to let the hell-spawn's LOVE reach 20. However instead of turning to dust, Sans felt himself beginning to melt. It was expected after all... he did have liquefied Determination inside him for god knows how long... he couldn't figure out exactly why he had it, just that he did.
Sans fell to his knees, the melting starting to become worse. The sound of the hell spawn's shoes walking off ahead the only sound happening in the golden halls of the final corridor. The hell-spawn in the form of a human child was making their way to kill the king... letting Sans know he failed once again. The small skeleton began to fall forward onto his face... but something stopped him. A pair of hands was what he felt holding him up from the dark orange tiled floors.
"Sans..." a familiar, yet not familiar voice spoke with a quiet, yet echoing voice. Sans didn't know, why but it calmed him... and made a few tears start to form in his eye sockets. He wanted to question the voice, ask them who they were... ask them why they knew him but he was fading fast. His legs feeling like they were melted down already.
"I'm sorry... Sans..." the voice spoke again, as Sans felt himself be pulled gently into what he could only assume as a hug. As Sans felt his world darken as the rest of his body melted, he heard the voice one last time, this time not as faded or as Echoing.
"I will fix this myself."
...
Chara grinned as they controlled the body of Frisk. They had just killed Asgore, once known as their father and had just cut Asri- no Flowey, they had to remind their-self on that one, down into nothing. Now nothing could stand in their way when they went back to the surface. They took one step forward, only to jump back quickly as a wall of strange looking bones shot up from the ground, blocking the only way out of the underground.
Impossible! Chara thought, knowing only two monsters with bone magic... and knowing that both were dead.
"You've done a real number down here... Killing my sons as well as every monster who got in your way..." an unfamiliar voice spoke, causing the child to turn themselves around and face the speaker. A tall skeletal looking monster stood there, two clear cracks going across his head from his misshaped eye sockets adding to a slightly more intimidating appearance. He seemed to wear a large blacken cloak... that appeared to be made out of the very shadows themselves as it moved unnaturally.
Chara held their ground, pointing their sharp knife right to the unknown monster before rushing at him for an attack. This was however stopped by the familiar feeling of Blue magic hitting their soul and lifting them up into the air, the same way Sans's had not to long ago.
"Do not think you have control here... Murderer."
Chara was preparing to bounce back from wherever the skeleton would throw them, but was not prepared for the Gaster Blasters to surround them as they floated there helplessly. A large purple energy began to form in the blasters, instead of the blue that was more known from Sans.
"Die."
The Blaster Fired, making the possessed human scream out in pain as the soul shattered and prepared for a new reset. However right before Chara or rather the player could hit the continue, the unknown skeleton popped up in the darkened void of the screen.
"The next time you try and kill everyone here... you'll be in for a nasty surprise from beyond the void. I'll be waiting for that choice."
When the screen returned to normal, it was as if all the saved data... had been erased as the "Name the Fallen Human" screen came up instead.