SORRY FOR THE INACTIVITY!!😓😢
Here's a chapter to make up for it. It's set a month after Sans lost his memories. Also I have no idea if this is going to be canon to the story or not so…yeah
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"SANS! COME ON DOWN!! WE'RE WATING!!"
"I'M COMING PAPYRUS!!''
Halloween. It's the time of year where everyone dresses up and go trick-or-treating. For me? It's the time of year where I dress up as a pineapple. Because Frisk forced me to. Why do you do this to me Frisk? Just why?
"Well, well, well, now who lives in a pinapple?" Toriel says when I come down. I'm very confused by that phrase.

"Uh, wha?" I say.

"Oh, right, you wouldn't get that reference."
I decide not to question it, as I already have too much in mind. Mainly the fact that everyone I know is in the room watching me in a pineapple costume. I feel myself blushing like crazy with embarrassment.

"Wow, nice costume Sans." Undyne says, trying to hold a sniker(hope I spelled that right). She was wearing a costume that has a blue jacket with some denim jeans(Ash Ketchum). Alphys was wearing really pink dress with a huge bow in the center and some cat ears(Mew Mew Kissy Cutie). Toriel was wearing a witch costume, and Asgore was  Frankenstein. Papyrus was dressing up as Frisk, and Frisk is wearing a purple pony costume with a horn and a pair of wings(Twilight Sparkle).

"Alright, what are we going to do?" I say trying to change the subject.

"W-Well," Toriel started saying, trying not to laugh at me. I can tell. "Ahem, we are going to go supervise Frisk while she trick or treats, and then we are going to the halloween party downtown."

Great. More people are going to see me in a pineapple costume.

"Huh, Frisk? What is it?" Toriel ask, as Frisk is pulling in her dress.

"Can Sans come with me trick-or-treat while you go to the party?"

Frisk don't do this to me please. Just don't.

"Well, I don't know…"

"OF COURSE HUMAN! THE GREAT PAPYRUS ACCEPTS!!"
PAPYRUS(ಥ_ಥ)

"Now, now Papyrus, Sans still hasn't gotten used to the town yet. What if he gets lost or…"

"Aww, come on Tori, let him go, Frisk knows the way, right? Sans could just supervise her and they wouldn't get lost."

Toriel sighed"Well, alright,. As long as you stop calling me 'Tori', alright?"

Asgore put his hands up and put a cheesy grin on his face. "Hehe, right…"

"YYYYAAAAAAAAYYYYYYYＯ(≧▽≦)Ｏ " Frisk yelled.

"Well, w-we better get going, or else we will be late for the party." Alphys said.
Then we all headed out the door, and the cold breeze blew by, welcoming the night.
"Alright, be safe you two, be home by 10:30, it's a school night. Oh! And call if you need anything."
"Alright mom, love you!"
And we all headed out in opposite directions, leaving me and Frisk to trick-or-treat. This is going to be a loooonnnnggg night…
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"Happy Halloween!" The woman said, as Frisk and I leave her doorstep.

"THANK YOU!" Frisk said with a smile.

Heh, that was actually not bad. Actually, no one actually cared that I was dressed up as a pinapple, suprisingly.

"Come in kid, lets head home, it's almost time." I say, trying to hold her hand. But then a cold breeze fell, and it sent shivers down my spine. I blinked.

This isn't the town. Actually, it looks like we are in some kind of forest. I panicked, but luckily Frisk was there. Frisk helped me calm down.

"O-Ok kid, where are we?"

"I think, we are in the Ebott forest." Frisk replied, confused as well.

"Heh, that's right idiots."
(Can you guess who it is?🌳)

"W-who's there?!" I say, trying to find the sourse of the voice.

"Why…" the voice replied. It came out of the shadows, and it was…me. "i'm you." Huh, lucky guess. The thing is, it didn't exactly look like me. It looked like it was covered in some kind of goop, with tentacles coming from his back, four of them, and only one of his eye lights were visible, giving a blue glow. It scared me down to the bone.

"Stop it Nightmare, we don't want to do anything with you, so get lost somewhere in your castle!" Frisk said, filled determination.

"Kid, you know the guy?" I say, refering to the goopy me, which I guessed was called Nightmare. That is honestly the most suitable name for him.

"It's a long story, but for right now, stay behind me."

"Oh no your not kiddo, I promised Toriel to take care of you, and am not planning on breaking that promise."

Right there Frisk eyes were filled with fear, like she had a bad memory and it came back to her.

"Alright enough of this sappy stuff." Nightmare said, as he prepared to attack with his tentacles. He knocked Frisk into a tree, and Frisk's' horn bent.

"FRISK!!" I say, trying to run to her, but one of Nightmare's tentacles stopped me. I ended up falling from the impact.

"Any last words?"

I was paralyzed from fear. Is this how i'm going to die?

"I DON'T THINK SO!!" Another voice said, the figure falling from the trees, blasting a beam at Nightmare, making him jump and fall on his back. This figure also looked like me, except he had blue and yellow clothes, along with a bright blue cape. His eye lights were a bright yellow color. He definitely looked nice, but I kept my guard up. Then, he started waking towards me.

"Hey, are you alright?" The figure said with an outstretched hand towards me. Should I trust him? I thought. I mean, he did just save me. I decided to risk it and took his hand.

"Yeah, uh, w-who are-WATCH OUT!!!"
Nightmare quickly recovered, and was now attacking us with his tentacles. The 'nice me' knelt down and tried to protect me by wraping his arms around me. Then, a gaster blaster came out of no where, and it protected me and the 'nice' me. Then 2 more me's came out of the trees. One was running up to us, and was wearing a brown painter's outfit, and had a brown scarf. His eye light changes each time he blinked.  He also had a giant paintbrush, and looked like he was about to hit someone with it. The other one was helping Frisk, and was wearing an outfit similar to Papyrus, only it was blue and grey instead of it being red and white. He also had blue eye lights.

"Enough Nightmare, it's time to leave this AU!" The painter me said, getting ready to attack. The blue me and Frisk soon joined, all getting ready in a stance.

Nightmare became furious, and started using his tentacles again, making them sharp at its ends. The 3 'good' me's started running towards the tentacles. The 'blue' me made bones appear and used them to stop one of the tentacles from attacking. The 'painter' me shoot yellow paint from his paint brush, which hit Nightmare's other tentacle. The 'first nice' me summoned a bow and arrow, and hit Nightmare's third tentacle. The forth tentacle was heading towards me and Frisk, and she made a shield in the shape of a red heart. Nightmare's tentacles were all now stopped, and I just sat there in shock, trying to process what in the world just happened. Nightmare for some reason decided to leave right after that, summoning a portal, and giving the 'first nice' me a hated glare, and went through.

"…………OKWHATJUSTHAPPENED?!?!"

"Eh, Frisk will tell you." The painter me said.

"MWEHEHE, DON'T WORRY PINAPPLE!! YOU WILL BE JUST FINE!! OH, FRISK! ARE YOU COMIMG TO YOUKNOWWHERE FOR THE MEETING?!"

Frisk gave the blue me a thumbs up. And after that, painter me make a huge puddle of ink on the floor, and all 3 me' s jumped in.
After that I just stared at Frisk for a long while, until Frisk broke the silence by saying "It's getting late. I might know the way to the town. Oh, and Sans?"

"Y-yeah kid?" I responded.
"Never speak of this with mom, ok?"
We walked all the way back to the town, and the entire time my skull was filled with thoughts.
Who were those guys? How does Frisk know them? How on the world did Frisk make a shield out of no where?! WHY did't she want to tell this to her mom?! But the main thought in my head was…

Why did he have to call me a pinapple?
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And everyone at the halloween party were playing halloween themed Just Dance songs. Cause why not.🙂