Undertale AU Sibling Oneshots

Overprotective! Ink x Twin Sister! Reader

Requested by the lovely Some_UndertaleNerd!~

You huffed as Ink slipped away again, leaving you alone in the void of AUs. He'd never taught you how to use them, and you didn't want to break anything, whether that be yourself or the AU, trying.
Ink was very overprotective of you, and you were torn.
On one hand, you understood why. You were the only family he had left, he didn't want to lose you too, especially not with his arch nemesis running around wreaking havoc more often lately.
On the other hand, the man needs to know when to let you have some fun in your miserable life.

It was one of the rare occasions when Ink brought you along, this time you were visiting Underswap.
You saw your chance.
Ink was too busy talking to Swap, so you took the chance to slip away.
So far so good.
You wandered around Snowdin, seeing as this timeline was still underground. You enjoyed the gentle crunch of snow under your feet.
Eventually you found yourself in the snowy fields outside of Snowdin and the forest. You happily dug around in the snow poffs, giggled to yourself as you stumbled upon this AU's snow skeletons, and overall just enjoyed yourself in the snow.
That is, until your arm is entangled in blue strings.
"Oh... You must be Error."
"YoU'rE nOt Ink... yOu MuSt Be ThE sIsTeR hE nEvErS lEt'S lEaVe HiS sAfE hAvEn."
"He let's me leave sometimes," you expression turned sour, "So long as he's with me, of course."
"WhErE iS hE, bY tHe WaY?"
"Chatting with Swap! I snuck away to have some independence for once!" Your cheery attitude came back, a soft grin adorning your features.
Error raised a bone brow at you, releasing your arm from his hold.
"YoU'rE nOt ScArEd Of Me?"
"You haven't tried to kill me yet, have you?"
"FaIr EnOuGh."
"(Y/n)!? Where'd you go?"
You groaned, frowning as you muttered under your breath. "Why couldn't you keep talking with Swap?"
Just as you were about to turn to head back, Error tapped your shoulder.
You turned back to him, seeing him gesture silently to an open portal, a relaxed smile on his face.
You gasped quietly, your eyelights sparkling in your sockets.
"You mean it!?" You breathed, grin widening when he nodded.
Without a second thought you jumped through, laughing brightly as he followed you.
"DoN't Go OuT mUcH?"
"Ink never lets me go anywhere! He's too worried about my safety and all that..."
Error let out a glitched hum, guiding you along.

"Calm down, Ink! I'm sure she hasn't gone far." Swap tried to reassure the colorful skeleton, but it didn't seem to do much. (Swap dear, I'm pretty sure across the universe in a completely different AU is pretty far)
"But what if she gets hurt!? What if—"
"Ink. This AU is one of the safest! And you said yourself she can't use portals on her own, so what's the harm in letting her explore?"
"What if Error comes by!? You know he likes to attack this AU!"
"Oh yeah, that is a problem."
"Aaagh!"

"So which AU is this, Error?"
"OuTeRtAlE."
You hummed, finding yourself amazed by the nebulas above and around you, spinning in circles as you walked.
"It's so pretty!"
"HaS InK eVeR tAkEn YoU hErE?"
"Uh-uh. He's only ever taken me to Underswap really."
Error watched you for a moment, just utterly baffled by how fearless and relaxed you seemed around him.
"YoU'rE aWfUlLy CaLm... WhY aReN't YoU sCaReD? I cOuLd AtTacK yOu HeRe AnD iT wOuLd TaKe AgEs FoR iNk To FiNd YoU."
You laughed at that, turning to him with a closed eye smile.
"Oh Error," your eyes opened to show red slits for your eyelights, "You try to hurt me, and I'll rip you apart fiber by fiber. Ink may have the brush, but I have something much sharper!~"
Error began to sweat, his eyes hollow as a shiver raced down his spine.
"Now c'mon! I wanna go explore some more!"

Eventually, Error returned you to Underswap, and you began your merry trek back to Snowdin, trying to make it seem you had just been exploring the whole time.
It wasn't a total lie...
"(Y/n)!!!"
You were soon enough barreled into, Ink nearly crushing you in his hug.
"Where did you go!? You know I don't want you wandering off!"
"Ink I'm fine! I just went to explore! Besides, you said Underswap's the safest place to be, so what's the harm?"
Ink drew in a long sigh, hugging you once more. "At least you're not hurt. Let's head on home."