Lane of Jealousy: Yandere Frisk

Chapter 1

As the alarm began its insistent ringing, Sans cracked open his eye sockets to face yet another seemingly tiring day. He let out an exaggerated yawn, the sound echoing through the room, before sitting up and silencing the alarm. With a lazy smirk, he checked his calendar—yes, it was Frisk's birthday.

Sans chuckled to himself, realizing he had forgotten about it until Papyrus reminded him two days ago. He was always a last-minute guy, preferring to procrastinate until the last possible moment, yet somehow managing to get things done. How he did it, no one knew, not even him.

Teleporting outside, Sans glanced at the surface and the sun, still marveling at the fact that Frisk had truly freed them all. He felt a wave of gratitude wash over him.

Speaking of Frisk, he needed to find a present.

Sans lazily strolled down the streets, his hands in his pockets, scanning for something simple and, ideally, inexpensive.

After just a few steps, he spotted a store displaying colors and canvases in its window—a perfect gift for Frisk, who loved to draw.

Entering the shop, he was greeted by a smiling teenager wearing a French hat. Sans approached him with a casual swagger. "Sup, fella. Got any ideas for a gift for a human who loves to draw?"

The shopkeeper thought for a moment, then suggested a new pencil set that had arrived a few weeks ago. Sans, not wanting to strain his brain over it, bought the set and left.

Checking his watch, it was almost time for the birthday party. Sans teleported to Toriel's house and knocked on the door.

Papyrus greeted him with a smile, wearing a birthday hat. "Hello, brother! We're almost done with preparations! Did you get your present? I mentioned it a few days ago."

Sans smirked and showed the pencil set in his hands. Papyrus couldn't help but show his disappointment at how effortless the gift looked.

They knew they needed to hurry, as Toriel and Frisk could arrive soon.

A few hours later, they did.

As Frisk opened the door, a warm and loud welcome greeted all the monsters in the house. Frisk beamed with joy, and the party started.

Sans, not a fan of parties, sat in the corner. Frisk immediately noticed and approached him, as expected. She always sought him out, seeing him as a close friend, especially since he acknowledged her powers.

Frisk waved her hand and said, "Hello, Sans! It's so nice to see you here. Thank you for coming to my birthday party."

Frisk warmly smiled and sat beside Sans. Everyone knew that Frisk didn't like to be disturbed when talking to Sans, so they left them alone.

Sans smirked. "Have no bones about it, kid, it's nothing."

He handed Frisk the pencil set. "Happy birthday, kid. Here's my extremely expensive gift. Be careful with it, alright? I bought it from overseas."

Sans winked at the end of his sentence, and Frisk laughed at his joke, as usual.

Frisk gently took the pencil set and bowed her head slightly. "Thank you, Sans. It really means a lot to me..."

Frisk exhaled deeply and asked, "Say, after the party, would you stay here for a while longer? I have something I want to tell you."

Sans pouted slightly, then defeatedly sighed. "Oh well... make it quick then at least, will ya?"

Frisk nodded, smiling, before returning to the festivities. Sans, true to his nature, settled back and did what he did best—nothing, opting to take a nap instead.

Hours passed, and Frisk's party finally came to an end. Frisk waved everyone back warmly, and thanked them for their consideration.

Then she turned to Toriel and requested some privacy in the living room for a while. Normally, Frisk wasn't one to ask for such a thing, but since Toriel had faith in her and it was her birthday, Toriel simply patted her head and told her she would be out for a walk and would buy some groceries.

Frisk smiled and thanked her. As Toriel left, Frisk's gaze immediately darted to Sans, who was still asleep, looking rather neutral.

Slowly approaching him, Frisk sat beside him. Sans didn't flinch, so Frisk glanced at him for a while, gently caressing his skull.

Sans woke up within minutes, and Frisk repositioned herself slightly, removing her head from his skull and smiling warmly.

"Good morning..."

Sans looked around, then grinned, repositioning himself slightly away from Frisk and waiting.

Knowing Sans for years, Frisk respected his space and started her conversation.

"You know Sans... I've been thinking."

"...Alright... Honestly... I"

Sighing a bit, Frisk tried to calm herself down. Sans just stared at her, wondering about the awkward situation he found himself in.

Frisk spoke faster and louder suddenly...

"So! I... I want to say that, that I want to push our relationship into something... different."

"...into something... more."

Sighing, Frisk looked away slightly, before looking at him again, this time rather directly and full of determination.

"Sans, will you go out with me?"

Sans, finally understanding, took a few steps back and stood up.

A very awkward silence filled the room, and Sans stared at her in shock before finally answering.

"Kid, y'know, I am not really a lovey-dovey type. You can find better, eh? Why don't you try to find a human lover? It'd be better for ya, whatcha think?"

Sans said awkwardly, looking at Frisk to gauge her reaction.

...Frisk didn't seem to take it well at all. Her eyes cut through him, her fingers tensed on the bed as if it's going to break soon, and her overall questioning looks, as if she didn't hear the declining that Sans just gave her.

Or she... simply didn't take No as an answer.