Sans is the brother of Papyrus, He is also a major character in PhantomTale. He first appears in the forest in Snowdin.
In This Au, Sans with the everyone else, was in the ghost void for 8000 years, appearing outside with a new appearance, Sans was basically some sort of Ghost or Phantom, gaining new abilities. Sans is one of the most laziest monsters in the underground.
In the Epilouge of Genocide Route:
Sans talks to the player and says "Heh, You know everyone was already actually dead. Everyone died a long time ago." , "Frisk died along time ago too, I'm talking to YOU(yourself the player). You could reset and try a better path, but you probably won't come back after all your hard work."
In the Epilogue of the Pacifist Path:
Sans talk to the player and says "Hey you know I'd like to thank you for sparing everyone, but everyone was already dead a long time ago. Maybe that's why we're ghosts, I can't even remember how i used to look. "
"Saaans! who are you talking to?" Papyrus asks Sans. "No one Pap." he replies. "Oh ok!" Papyrus then walks off" "Welp see ya." Sans then walks off and leaves you to explore the underground.
Sans being a ghost, allows him to fly around and sometimes go intangible. Sans wears a hoodie sweater, with the hood always on. Sans has no legs, and instead has that squiggly thing(kinda like how the flying Dutchman has in Spongebob) or as i like to call them Ghost Limb. San's colors do not change however his hoodie is a royal purple with a ghostly green fur, and his hands are usually in the sweater pockets. When San's Pupil glows, it glows a bright bright greenish blue.
Flight: Since he is a ghost he has flight enabled, though he has his shorcuts sometimes he freely flies for fun.
Ghost Splat: Just a ball of ectoplasm that he usually throws to gross you out. does no damage, unless its a concetrated version.
Ectoplasm: this is a passive, it basically means if you walk through him or any other ghost you get ectoplasm all over you, its very disgusting.
His relationship depends on the actions whether its the genocide route or the pacifist route.
In the pacifist route, they're very great friends.
In the genocide route, Sans is killed and does not like the human at all
In the disbelief route, Sans loses all belief in you and destroys you.
Papyrus is Sans's older brother, despite Sans's pranks and puns, they are very great brothers.
Sans admire and cares for his brother alot. He reads him plenty of bedtime stories and leaves presents in the identity of Santa.
Sans and Toriel are very great friends and enjoy bad puns. They never really see each other face to face except in certain endings and/or during the ghost void entrapment. While not to make any promises, Sans compiles Toriel's request to protect any child from the ruins.
There is barely anything known about the two's relationship. W'D Gaster was a royal scientist who walked into the core, his own creation. There are rumors that Sans was there when he walked into the core. Sans may know alot about him. When the ghost void was activated Gaster was able to return to the underground.
None yet, fans made add if they want