Yandere!UnderLust!Sans X Reader [COMPLETED]

I'm a portal through worlds

      You and your brother, Frisk went back to the normal Undertale world. Frisk dragged you out from Underlust. You were relieved. Sans was very flirty and you didn't want to deal with him right now.
      Smiling, you entered a house near the house you and Frisk lived. The house was slightly smaller and was full of paint tubes, canvases and paintbrushes. Yup! This was your art studio. Plus, you left Papyrus and Sans stay there.
      But now, it's only Papyrus. Sadly, Sans sacrificed himself up to enstable the Undertale world. He's in every place except yours.
      "CHEER UP (Y/N), THIS IS NOT THE (Y/N) SANS WOULD WANT!" Papyrus said.
      You smiled," I missed Sans. The other Sans are not like my Sans
      Papyrus felt a twinge in his heart. He considered you as his daughter, note than Toriel did.
      Your glassy (E/C) orbs glistened with water. You cried in Papyrus' chest. Papyrus soothed you, telling you to calm down. He rubbed your (H/C) hair.
      "Also... Frisk has been a lot distant lately. I wonder...if that has anything to do with me?" You asked.
      Papyrus knew that the portal to Underlust was not stable. Frisk had been through a lot lately so he became distant.
      "TELL ME EVERYTHING (Y/N)," he said.
      You spilled everything out. Papyrus felt that you loved Sans, but the normal Sans. His eye flashed fuchsia for a split second.
      "NO! THE UNDERLUST, WELL ONE, ESCAPED!" Papyrus held his head, which is throbbing now.
      "S...Sans!" You whimpered
      Indeed it was him. He touched Papyrus' head and crushed it, making Papyrus lifeless.
      Your only father figure, Papyrus, lay dead in front of you. Your so called 'lover' held a katana, which is covered in blood.
      "well, well my little bloody do you love this blood? of course it's frisk's! do you love this katana? of course! it's from sakura shrine!" He said," joking its from your warehouse!"
      He smirked evilly while you were taken aback from what he said.
      "Frisk's dead! Frisk's dead you blithering idiot!" You screamed.
      Sans smirked," he did make a good wall decoration and it's nice seeing the life left his eyes." He stated," and now, my sweet little bloody (y/n), you will obey me forever, never disobey me since you know the consequences!"

Hey my friend Aicheu is only gonna make 2 chapters of this so yeah. I'm also thinking of making an alternate ending where it is happy.
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