Yandere Blueberry X Reader

Betrayal

3rd Person POV
~~~

Sans' eyes widened. His blue pupils shrunken and shaking of what he was witnessing.

(Y/n) was ontop on papyrus, tickling him. The both of them were giggling like two insane patients.

" Oh, what about there!? Are you ticklish there?! "

(Y/n) teased.

" Oh, Nono! Stop it! "

Papyrus laughed, clinching his eyesockets shut.
He tickled her back, (Y/n) laughing uncontrollably.

" You stop it! You're gonna make me pee! "

Both of them having tears of joy in their eyes.
Okay this was hurting.

" AHEM "

Sans had finally made his presence known.
(Y/n) stopped tickling papyrus and looked up at him.
She jumped off of the bigger skeleton and greeted them.

" Hi, Blue! How was your day!? "

She asked.
Papyrus sat up chuckling, still having the giggles from their 'friendly' tickle war.
Blue twitched a bit before realizing his queen was asking him a question.

" Oh it was alright! Training was great! How was yours?? "

They asked with a big smile, bags forming under his eyes.

" It was good! I had Papy to keep me company! "

You said happily, looking back at the taller skeleton.
Sans cringed at the nickname.
Sure, you weren't the first to come up with it but, pet names were a sign of liking someone.
And Sans didn't even want (Y/n) to consider anybody besides him close to her, let alone a friend.

" T-thats good. D-dinners ready. "

It was hard to hide the heaviness in his voice but (Y/n) didn't notice anything.  Sans was feeling a sudden slash of betrayal.

" I can tell! Smells yummy! "

You said walking passed him, down the stairs.
Papyrus fixed his sweater, pulling it down.
Sans stared him down. Papyrus felt the pair of eyes. He looked up at his brother and raised his brow.

" What? "

He asked.

" You know what. "

Sans said, his usually cheery aura replaced with a menacing gloom.
Papyrus sighed.

"Sans. This is too much. I feel as if you're growing an obsession with the human."

Papyrus explained.

" So what? I found her! She's mine! My human! Not yours! "

Sans argued.
It reminded Papyrus of when they were younger and would fight over the silliest reasons.

" She's not a shiny toy Sans. She's a human. That's worse. "

Papyrus stated.

" What if Alphys finds out about her? What then? "

Sans didn't say anything. He just pouted.

" I'll think of something... "

He mustered.
Papyrus closed his eyes shook his head. He sighed in frustration.

" Sans are you like this because of a silly little crush? "

He finally asked the big question.
Sans blushed a dark blue.

" Well- I...I wouldn't say crush- I just really really....like her... "

He finished blinking.
Sans had realized what he really wanted. At first he saw the human as a friend till the end, someone who would be loyal to him no matter what.
But now he see's that he wants more than a best friend. He wants...