Sans X Monster Reader

What happened?

You woke up in your apartment. Confusion crept into your head, hadn't you just heard someone laughing? Closing your eyes tightly you tried to remember...
~flashback~
"HELLO Y/N!!! WOULD YOU CARE TO PLAY IN THE SNOW WITH THE GREAT PAPYRUS AND FRISK?" Papyrus shouted as you approached. You smiled and picked up a snowball, chucking it lightly at the taller skeleton. You enjoyed the time until you heard a laugh behind you. You turned to see another human. They had brown hair, a green and yellow striped shirt, brown pants and boots, rosy pink cheeks, and piercing crimson eyes. "Hello... Frisk" they said, their voice echoing like the spoke in a cave. The other human was surrounded in a black mist, and held a knife in their hand. Papyrus, being a good royal guards, stepped infront of Frisk and you in attempts to defend you from the odd threat. "HELLO HUMAN. I AM THE GREAT PAPYRUS OF THE ROYAL GUARD... HOW MAY I-" Papyrus began before the human dashed forward. They moved so fast, that Papyrus couldn't block their attack. You and Frisk watched in horror as Papyrus' head slid off his neck, before his entire body and soul vaporized, leaving his bright red scarf in the snow. You saw Frisk read out and grab it, tears forming slowly. You stood in a defense position infront of the small human, but to no avail. The dark figure rushed you and stabbed you in the gut, dropping you to 1 HP. Frisk cried out to you and held onto you as the figure approached. "Don't worry (Y/N)... I'll fix this" he said as you saw two rectangles appear. One said 'Continue' the other 'Reset'. Frisk slowly touched the Reset and everything went white.
~End Flashback~
"What did Frisk do?" You wondered out loud as you got out of your bed. Looking at your calander, you noticed today was different than you remembered. Shrugging it off slightly, you got yourself ready to go out and began a small journey to the skele-bros home.