Undertale AU Sibling Oneshots

XTale! Chara x Twin! Reader

(finished Underverse Season 1 finally!!! So the events are obvi gonna differ slightly. (Also I know there's like, 10 different animations for XTale itself, I have not watched those yet) Now I need to catch up on Glitchtale, which is gonna take forEVER)
(but no seriously, I need to hug X!Chara, that poor child.)
Requested by the lovely corvid, Nightislost!~

(Like Chara and Cross, you know about the multiple timelines!)
(Also the only physical difference between you and Chara are your eye colors)

You could only guess Gaster didn't like you, or saw you as something that shouldn't have been. He had been talking about 'Overwriting' the AU, and just before he did so, he dragged you away from Chara, and tossed you through a portal right in front of them.
Apparently, he had Overwritten the AU multiple times, and in the most recent one, IX (9 in Roman numerals, X is 10), you had somehow been overlooked in the build and had ended up growing up with Frisk and Chara.
Gaster had a mind to immediately Overwrite the AU for... as he called it, 'this oversight', but he ultimately decided to have the AU play out. Overtime, he seemed to have grown an interest in you, seeing how you were unique as a third Determination soul, but also a near copy of Chara.
A twin, if you will.
So, when he grew tired of the timeline he had built, he tore you away from Chara's arms, tossing you into another AU, and the last thing you saw of home was him, Chara's weeping form, and the AU glitching away behind them.
That bastard had tossed you carelessly into the middle of some random AU, leaving you in the scary undergrounds instead of the big open sky you were used to.
You jumped up from the snow, tears already leaking from your eyes as you spun in circles, expecting a monster to pop out and attack at any moment.
Nothing but the silence, the cold, and the trees surrounded you and finally you dropped to your knees, sobbing into the snow.
You shot up at the sound of footsteps, whirling around to find the source.
"Woah! Hey, hey, hey," your eyes locked onto two skeletons, one in blue and one in orange, "It's alright, we aren't gonna hurt ya!"
Tears tracked down your cheeks as your vision flicked, instead of the lookalikes before you, you saw your Sans and Papyrus, a distant memory of when they found you all scraped up from a bad fall.
"Are you alright, kid?"
You blinked, and it was back to the orange and blue skeletons. A sob ripped itself from your tight throat, fresh tears tracking down your face. Your hands raised to hide them, which gave the Papyrus-lookalike the chance to scoop you up.
Feeling oddly safe there, you buried your head into his shoulder.
"Will they be alright, Paps?"
"Mmm, maybe. Let's take them back to the house and get them calm first."

You sniffled quietly, giving a quiet 'thank you' as you were bundled up and given hot cocoa and sweets from a place called Muffet's.
"Don't mention it." Lookalike-Papyrus grinned, patting your head.
"Hey Paps?" Lookalike-Sans muttered, almost too quiet for you to hear.
"Hmm?"
"Don't you think they look a lot like the human?"
"Yeah they do."
The human...?
Did this AU have a Chara and Frisk as well? Or maybe even an alternate version of you?
The three of you perked up to the sound of the front door opening.
Looking over, you nearly spit out your hot cocoa. Chara stood there, looking confused at the sight before them.
But it wasn't your Chara...
You vision flickered again, a split second of your Chara before you, and then back this the one in this AU. This Chara sported a green and yellow striped sweater, and their hair was brown instead of white.
"Chara! Come sit!"
Hands shaking, you quickly set the mug down before you dropped it and made a mess, feeling more tears fall from your puffy eyes and track down your red cheeks.
"What's wrong?" Lookalike-Sans asked, moving to carefully sit next to you.
"You wouldn't believe me..." You mumbled, scrubbing at your face with the insides of your wrists.
"Try us." Lookalike-Papyrus replied, sitting criss-cross on the floor as their Chara plopped down into his lap, who gave you two encouraging thumbs up.
You sniffled, taking a moment to collect yourself.
"I... I came from a different world. It... It feels a lot like this one. I grew up with... with people and monsters that look like you, f-feel like you. I had my own Sans and Papyrus, my own Toriel, Asgore, Undyne, Alphys, and Mettaton... a-and I had my own Frisk and Chara..." You couldn't stop your tears anymore, so you busied your tear-soaked hands by clutching the heart locket around your neck. "B-But h-he was in control of it all!"
Through your blurry eyes, you saw Lookalike-Papyrus tense, as if knowing who you were talking about.
"Control? What do you mean?" Lookalike-Sans murmured, clearly holding back from touching your shaking form.
"He could control the timeline, he controlled what would happen and what route the timeline would take. I was nothing more than an anomaly to him, an oversight in his creation. S-So, when he planned to restart, t-to Overwrite, he tossed me here, most likely to prevent me from coming back..."
You shook, feeling rather than hearing the silence that followed your next words, your (e/c) eyes turning lavender with your swarm of emotions. "I can't forgive him!"
You shut your eyes, feeling the fresh wave of tears fall. At this point, you wanted nothing more than to curl up in your Toriel's arms and listen to her quiet lullabies.
You gasped softly at the gentle arms that surrounded you, this AU's Chara hugging your tightly.

* Chara says they're going to help you get home.

You sobbed into their shoulder, clinging to them like a lifeline.
After a bit more talk and questions, Lookalike-Papyrus scooped you up, carrying you upstairs so you could sleep and rest.

~Time skip~

You walked hand in hand with Muffet, trying to find a good place for her to set up her bakery on the surface.
"I think that place over there is vacant." You said, pointing to a decent sized lot, which had 'For Sale' signs posted.
Muffet smiled at you, patting your head and beginning to cross the road with you.
You both were stopped however by a loud commotion, coming from the area where all the other monsters had gathered. Without a second to waste, Muffet scooped you up and ran back to them.
You scrambled out of her hold as soon as you saw Toriel, nearly faceplanting on the ground in your waste to get to her.
"Toriel!?" You exclaimed, eyeing the cut on her cheek.
"I'm alright, child. It's not too serious." She soothed, resting her paw on your head.
"What happened?"
"A monster attacked everyone in the town centre, Papyrus, Sans, and Chara went after them."
You looked off to where the destruction led, and after a moment of decision, you ran off after them.
"(Y/n) no!"
You ignored them and pressed on.
As you ran, the ground glowed white, then faded to purple.
You knew this magic!
Something thrummed in your soul, urging you to ran faster, and as the group of Papyrus, Chara and... multiple Sanses came into view...
You stumbled to a halt, tears tracking down your cheeks.
Chara was there, your Chara.
Not even the octopus or paint brush Sans distracted you, nor the weakened state of Swap Chara.
No, your eyes were locked onto your sibling, your twin.
"C... Chara!!!" A waterfall of tears fled your eyes as you bolted forward, ignoring the shouts behind you.
You enveloped your twin in a tight hug, quickly soaking their shoulder with your tears.
"Are you alright, (Y/n)?"
"I'm alright. A-And you?" You sniffled, earning a nod.
Your twin glanced off towards the goopy Sans for a moment, meeting your gaze again.
Their eyes were different, but that didn't matter.
"I'll explain what I'm doing later. For now, I need you to trust me."
You could hear the Swap trio shouting at you, telling you to stop and run.
You ignored them, taking your siblings hand. "I'll always trust you, Chara."
Chara grinned, squeezing your hand back and moving to stand next to you. "How much do they trust you?"
"Probably not at all anymore."
Chara lifted their blade, grinning. "Long story short, our AU is gone, and I'm rebuilding it."
Summoning your own blade, you lifted it like Chara had done. "I'll help then."
"And he won't be apart of it." You both spoke in unison, slamming your weapons into the ground.

(Three more requests after this one, will most likely take a small break from taking so many requests so I don't feel like I'm constantly swamped y'know? Requests will still be open tho!)
(Including the bold text, there is 1542 words in this oneshot. My longest yet?)