When two soul mate meet.. their soul remember each other and never forget..
Sans doesn't believe that at first, well.. that's was before he meet Frisk...

Surely he was a monster who doesn't have any care for the world except for his brother and friends, he comfortable with his life and doesn't have any plans to change it... then one day he meet Frisk...
That day he just sit behind his hotdogs stand like usual, then small goat looking monster come running to him with huge eyes.

"MR!! MR!! i want hotdogs!!"

Sans grin at him and hand him a hotdog, surely this little monster just move here or something, because he never see him around before.

"How much it is sir?"
"You must be new here huh? nah.. just think it's my welcome gift kay"
"Really!! thank you!!"

The little monster jump up and down excitedly but then let out a 'Uffh' sound when someone lift him up and hug him from behind.

"Sis!! look i found a very nice monster today!!"

She giggle and ruff his head, welp... Sans think that's must be another monster who move with him, he made another hotdog for her and when he want to hand it he froze. Stond in front of him a human that look very cute, she hug his small brother in her arms.

"Thank you for giving my brother the hotdog, he looks so happy"
"Uh.. uh.. sure thing..."
"I'm Frisk by the way and this little guy is Asriel"
"Well... I'm... Sans.."

She smile at him making him blush, Sans never be the one who easy to blush but now.. he feels kind of weird.

"Well Sans! see you around then!! it's nice to meet you!"

She run away with giggle while Asriel keep laughing with her.

"Sure..."

Sans still froze there while holdings a hotdog in his hands... well the sight of him is rather funny actually...
After that Sans discover its true that they just move here and fortunately they are his new neighbors. Papyrus, Sans brother are very excited to have a new neighbors and cook for them his famous spaghetti... that's famous because if someone actually survive eating that, well.. you can begin to clap your hands for them then.

Sans watch her take a first bite to the spaghetti and of course Paps still staring at them with hope in his eyes. The spaghetti is burned and have many sparkles in there..i don't know if it's right to call it spaghetti or not... Frisk bite into it and flinch a bit but then she smile and give a thumbs up to Paps, but of course Sans see the truth and chuckle a bit.

"This is good Paps, thank you"

Paps then run to the kitchen with joyful yell, he begin fo make more spaghetti... well hope this time he didn't add a cupboard.
Day by day passed and Sans feels more and more attracted by Frisk, honestly he glad she was shorter than him or else he will surely wear mettation high hells everyday...
Frisk is kind, beautiful, soft, and all he could wish for but he didn't have a guts to ask her out... well... maybe he just afraid that if she reject him then they friendship will break.

Then one day, Frisk bravely ask him out.

"I love you Sans.. do you want to go out with me"
"Gezz.. kid.. i- i the one who suppose to ask you out"

He cover his face with his hoodie feeling so happy and embarrassed in same time, Frisk kissed him and he kissed back... that day Sans feels like he got a new life.
Sans chuckle remembering that time when she ask him out.... hmm... when is it... oh yea! 5 years ago. Sans feels happy smile blooming in his face, he hold a small box in his hands, this day.... he will ask her to marry him after she come back from her trip to her old country.

Sans eyes soften when remember how well she treat him, she never mad at him and always understand what he feels... really... Sans know he not a great person (skeleton) so if it's cost all his life to meet her... he will give it anyway.

His happy mood get cut by his phone that's ringing loudly in his pocket, with lazy gesture he pick that up and he find Frisk brother, Asriel in other line.

"Sup?"
"B-bro... *snif* F-frisk"

Sans soul thob with ugly feelings

"What happend?"
"My sister and i are on the deck when storm comes, S-she save me from the wave... but he get thrown to the s-sea"

Sans can hear Asriel cried now but he can't think anything.. just blank..he dropped his box and teleport to the Asriel who hugging himself on the ground. Sans body shaking... this can't be happening.

"Asriel! answer me.. where is she!!?"

Sans shake him hard, worries keep eating him slowly and Asriel state didnt help a bit, with sad emty eyes, Asriel look up to him and cry.

"She is missing"

Sans tears fall and then he scream while griping his head... that day suppose to be the happiest day for him turn to be a disaster...

Where are you Frisk?