This lore when the players tries to hack the Undertale: Neutral Run, and eventually something wrong with him, and starting torturing himself and died, leaving in Waterfall is becoming abandoned.

Stage 1: Torture Him and Rip apart of Him.

Sans introduced himself to Abused.666, and tries to cutting himself, and the pain is killing him with the routes, he doesn't want to talk about it or he's just depressed to end his life for his suicide.

Stage 2: Y̴͉̦̩̓̉Ó̷̺̝̔͗͌̃̒U̸̡̪͋͗ ̵̧͇͠W̶͕͔̮̟̊̎̀̇̃̈I̷̳̭͊̐̑̿L̵̘̥̽̇͛̑L̷͈̔̃̿̔͒̉ ̵̨̥͈̖̉̿̔̕͠R̷̦͖͈̓͌̐̎̊̚E̷͓͓̠̺̾͗̐͂G̷͓͚̬͌̓̐̀̿̕Ř̷̮͖̋Ė̵͍̗̳̻͙͌̔̋T̵̤̀ ̶̧̣̜̈́͒T̵̨̺̬̣̘̈́H̶͇͖̱̏̃̋I̴̱̙̯̽̒͊̚Ŝ̵̳̟̦͓͂.̴̯͚̌̈́̏

After the player hit him, he dodged and sans starting to a little bit hostile, his eyes were melting with white eyes and covered with blood, the entire Waterfall is in incident of suicide corpse, and he says strange things: "You're life has ended, brat."

Inspired by @takwa764 analog horror.