Just a very big love (AU sans x reader)

Haunted by old memories

(Y/N)'s POV

You were just being lazy again by Cross Chara who was completely out of their mind talking about timelines and timelines and timelines. You grew bored as you stood up and walked to the exit door and exited the skele-bros house. You really wanted to meet Error or maybe Ink again, as you decided to call for one of them

*You called out Error's name hoping he would hear you

You waited so long until a portal was right below you and you got sucked into the portal. As darkness surrounds you, you panicked and tried to move your legs and hands. You can't feel anything as the last thing you saw on your vision  was a skeleton in green and a giant flat wall-type paint brush and you close your eyes, drifting to sleep.

~P.T Sans POV~ (didn't see him here aye?? *lenny face insert*)

I heard a large crash on the other side of the void. 'Don't tell me is that Ink guy', I thought. As I walk where the noise came from, I saw a girl. Not just any ordinary one, but a beautiful girl. She was knocked out. I immediately went over her and carried her in bridal style. Her (h/l)(h/c) hair is magnificent like paint, her (s/c) skin is as soft as snow. I put her in a spare room that I have at home and laid her on the bed. I went out of the room and close the door carefully, not wanting to wake her up. I went downstairs, into the kitchen as I made her some sphagetti and pour a glass of water. 'Why do that girl look so familiar???' I thought as I remember who she was to me....

My very own best friend

~(Y/N)'s POV~

You whimpering like crazy from the nightmare you had right now. And that green skeleton with the giant flat-wall type paint brush was in it. So many questions were asked in your head.

Who is that skeleton??

Why does he look familiar??

Is he a friend of mine in the past??

Or just a frenemy that I never knew??

Your head was filled with questions until you flashbacked a memory which you never expect to be played in your mind....

Flashback start

You were with that green skeleton, both of you were playing in a large, open field. You were 5 at that time and that skeleton looks like 9 or maybe 10 ,"Don't be scared Paint Thinner!!"  Your young self exclaimed, "I don't know, (Y/N). I think they will tease me..." The green skeleton that you called Paint Thinner said in a sad and drowsy voice. "C'mon Paint Thinner!! They won't.. Besides if they tease you they have hell to pay!!" Your young-self said as you saw your young self holding a knife. "Whoa whoa, (Y/N). No need to be violentic.." Paint Thinner replied in a scared voice. "Sorry I'm trying to hold the bad side of me though... By the way, when will you show me the Classic Sans??" Younger self you ask, "Well... maybe never?? Cause.. Every AU Sans teases me for the person or should I say skeleton I am.. Even Ink teases me.. I thought he was going to give those other Sans hell but I was wrong.. Even know I'm like Ink, a creator, but he said that I'm weak to be one.." He sighed and started to form tears. "Don't cry, Paint Thinner... I'm here for you!!" You cheered. Paint Thinner smiled, "Promise me you would never leave me...??" He askes and make a pinky promise. "I promise.." You smiled and pinky promises with him..

Flashback ends

You jolted up from that weird dream you were having. You stood up from the bed and goes downstairs. You smelled something delicious from the kitchen as you saw the green skeleton who you thought that it is Paint Thinner. He looks at you and smirks, "Awake already.... (N/N)??" He asked as you nodded. "Paint Thinner..." You inhale some air and exhale it as you sighed, "I'm sorry for breaking our promise... I shouldn't have left you alone" You apologized to him as you heard a chuckle from him, "Oh it's fine (N/N).... Besides, I already knew you would came back to the underground" He said as you tilted your head in confusion

Came back to the underground??

What did he meant by that sentence??

He stop smirking and looks at you, "(Y/N)... When all AU's of Frisk died.. All of the Sans including me went into despair, leaving us sad & depressed. Legend said that a human girl will fall down to the underground and will cure a monster's mental disorder.." He explained. "We, the Sanses, knew the monster must be us. But the human girl??? We thought that it was Frisk... But we were wrong. It wasn't her.." He said,looking away from you. "Do you want to know who's the human girl??" Paint Thinner ask and smirks at you. Curiosity got to your head as you nod your head quickly, "As curious as ever I want to know who's the girl..." You said as you saw his black pinpricks disappear. "The human girl.... Is you (N/N)" He said. You widened your eyes in shock

'How could I be the girl??' You barked at your thoughts, which were running on your mind with questions about the legend.

"Well (Y/N).. I guess it's up to you to achieve your goal as the legend. To make us,the Sanses, happy again.." Paint Thinner smiles. You nod and look at him "Hey Paint Thinner??? Can I ask you something??" You told him as he nodded, "Fire it away.." "Well how could I make every Sans happy??" You ask him as he thought for a moment. "I don't know.... To make us in love with you I guess" He shrugs as you blushed slightly.

'Make them all in love with a human girl like me?? Pfffff... No way of course that's impossible.. Sans is a skeleton and I'm a human... That is the most stupidest thing ever!!' You barked at your thoughts again.

You didn't realize that maybe Classic was worrying over you "Hey Paint Thinner?? Can you teleport me back home at Undertale??" You ask him as he slightly nods. "Sure.. Let's go!!" He said and snaps his fingers as he teleported you back home at the skele-bros house, "Thanks Paint Thinner I'll visit you some time" You smile as he nod "See ya!!" He said and teleported away. You heard footsteps running towards you as Cross and Classic hug you and said together "WHERE WERE YOU??" They spoke in a mad tone as you giggle and tell them the long story

(whew that's a lot of words.... so yeah see ya in the next chapter byeee!!!)