Cold Lust (Yandere Underswap! Sans x Female reader)

Betrayal

*This Chapter will have a little bit of fluff just a warning for the kiddos*

Your POV

"Hey, Y/N," I heard Papyrus say from beside me.

"Yeah?" I replied.

"Do you like anyone?" He said, as I choked on the candy I had gotten myself.

"Um...y-yeah," I said a little worried.

"Who is it? I promise I won't tell," he replied in his usual, laid back, tone.

"It would be a little awkward..." I replied as a scratched my shoulder.

"Ah, c'mon Y/N it's fine," he said in a puppy dog voice.

"Fine, but don't tell...i-it's kind of two people..." I said with my head down.

"O...kay..." He replied.

"It's...Sans and you..." I said as I put my head down into my hands. I waited for him to reject me, but I felt something slide around my waist. I suddenly was pulled towards Papyrus. I looked up to see that I was only a few inches from his face. I felt my face blush bright red.

"Well, then I'll just have to persuade you to be with me~" he said as he leaned down.

"Wha--!" I said before I felt his teeth hit my lips, supposing it to be a "kiss." My eyes widened, but I slowly melted into the kiss. I wrapped my arms around his neck, and was surprised when I felt something wet touch beneath my lip. I gasped, and the slimy appendage slid into my mouth, I tried to fight for dominance, but quickly lost. He used his tongue to explore every inch of my wet cavern. When I pulled away, there was a long orange and clear strand of saliva connecting us.

Sans' POV

I was ready to walk down stairs to greet Y/N and Papyrus, but I stopped in my tracks when I saw Y/N and Papyrus on the couch kissing! How could Y/N do this to me! She was supposed to love me, not my brother! I stood there furious for a few seconds, but calmed myself, and went downstairs went I saw them end their kiss.

"HEY PAPY! HEY Y/N!" I said as I reached the bottom of the stairs.

"Oh, hey bro," Papyrus said.

"Hey Blueberry!" Y/N said in her usual angelic voice.

"PAPY, CAN WE GO TO THE STORE AND GET SOME TACOS?" I said in my cute voice, using my puppy dog eyes.

"Sure, but I want you to stay with me wherever we go," he said as he held out his hand for me to grab. I took his hand and we teleported to the store. I bought some taco ingredients, and started to head home.

"Hey Sans! Don't wander off!" I heard Papyrus say from behind me.

"I'M NOT! I'M HEADING HOME!" I replied. Papyrus was next to me and we walked together home.

Skip to 20 minutes in the walk (the full trip is 50 minutes.)

I stopped walking, and Papyrus seemed to notice.

"You okay bro? You tired?" He said as he came over to me and put a hand on my shoulder.

"You think you're 'all that' don't you?" I said in my darker voice. I felt Papyrus take his hand off my shoulder.

"W-what do you mean bro?" He said in a confused but scared manner.

"You think you can just take Y/N from me? She's M I N E!" I said with my freaky grin.

"Br-Sans, you know she likes both of us right," He replied.

"Well, only one of us can have her, and she belongs to ME!" I said as I flung my bone attack at Papyrus. He seemed surprised and just barely missed the attack.

"I understand now...it was you!" He said as I saw his eye flare orange as orange tears fell down his face.
"You were the one that killed everyone." He said in a furious tone.

"Oh, how clever of you, you figured it out," I said as my face turned into a wicked smile.

"Fine, if you want it to end like this, then bring it on," he said as he started to fight me. He threw a few bone attacks that were obviously easy to avoid. I sent a few gaster blasters that almost got him, but barely missed. I then surrounded him with gaster blasters.

"Goodbye D E A R B R O T H E R!" I said as the gaster blaster fired. When the smoke had cleared, I could feel this smile growing on my face. Where Papyrus had stood, there was now a pile of dust. I started to laugh, but then I heard the most gut wrenching thing.