Fatal Error Sans

Fatal Error is a skeleton monster. His height is +-122 cm. His body and voice are very glitchy and distorted. His right eye is slightly melted and red with a code inside, and his left eye is whole and blue, also with a code inside. When he is angry, his glitches become stronger, his voice is more incomprehensible and both eyes become red. A thin stream of blood with small lines of code on it flows from his mouth. He wears a red scarf, a black T-shirt with a slit across the entire waist, through which you can see a huge scar also across the entire waist, a white unbuttoned jacket, black shorts with two white stripes on the sides, white slippers with blood. There are barely noticeable lines of code against the background of all his clothes.

In one of the Undertale timelines called Aftertale, Sans decided to inject himself with determination before fighting a human. He injected so much determination that a "Reset" button was revealed to him. Sans killed the human many times, but he could not reset everything to the beginning because he injected determination too late. Eventually, the human managed to hit Sans. However, instead of dying, Sans was sent to a loading screen. He could not exit it, because if he did, he would die, since he had low HP and only 1/9 of his soul. He decided to call himself "Geno Sans", and the word "Geno" in his name is an abbreviation of the word "Genocide"

Geno Sans was in the loading screen as usual, but suddenly Error Sans came there with the intention of killing Geno. Error tied up Geno, but the latter warned him of the consequences, which Error did not listen to. Geno's existence was already abnormal, and after his death, it became even more abnormal. Geno began to glitch heavily, he began to have constant mood swings and he became the vengeful spirit of Geno Sans named Fatal Error Sans. He ended up in a place with flowers, then got into the Anti-Void, where he met Swap Sans. Fatal was amazed by Swap's kindness, but due to his instability and madness, he broke the latter's arm.

From the blood stream from his mouth, he can produce red threads that he can use to entangle other creatures, causing pain. He can summon Gaster Blasters, which are just as glitchy as he is. He can summon glitchy bones of different colors that deal a lot of damage. He can teleport. Upon death, he will immediately be reborn. Normal creatures are unable to damage him.

Take revenge on Error Sans. Return Papyrus (younger brother)