Mistake

Car: sports car (you can choose a specific model or leave a fictitious one).
Color: Bright white with multicolored paint splashes across the body, as if Ink painted it himself. The hood may have traces of blue, yellow, red, and green paint.
Machine features:
looks nice, but not always reliable;
inside there may be brushes, paints and Inca's things;
Small glitches may appear on the dashboard due to the presence of Error;
The car often causes Error to panic due to Ink's driving style.

Ink's main ability is to create objects and elements of the world using paints.
It can create:
weapon;
objects;
designs;
various artistic elements.
ability from paints:
Ink is able to use paint as a weapon:
create attacks;
to form a defense;
change the environment.
teleportation:
He is able to travel between alternate universes.

With Ink paint bottles usually:
funny;
vigorous;
curious;
friendly;
creative;
loves to create new stories.
He loves art and new ideas.
But there is a more complex side to him.
Without emotions, Ink becomes completely different:
cold;
indifferent;
unable to understand the feelings of others normally;
more like an empty shell.
He's neither a hero nor a villain. His actions can be questionable because he cares more about preserving stories and creativity than about moral rules.

Paints and bottles
Paints are one of the most important parts of Inca.
He carries special vials of different colors. These colors give him emotions he lacks due to his lack of a soul.
Without colors, Ink becomes cold, empty, and almost completely devoid of emotion.
With colors he can feel:
joy;
inspiration;
sadness;
anger;
fear;
other emotions.
This is why his cheerful nature is not always a natural part of his personality, but a result of the influence of colors.

Ink Brush — Broomie
Inca's main weapon and tool is a huge brush named Broomie.
This is not an ordinary painting brush.
Broomie is used as:
weapons in battle;
creation tool;
paint management method;
a means of changing the surrounding world.
With Broomy, Ink can create various objects, attacks, and elements of reality from paint.
(Broomie can't speak because it's a brush)

Ink!Sans appears as a short skeleton with white bones and a vibrant art style.
Its appearance is very different from the usual Sans:
multi-colored paint stains on the body and clothes;
bright elements of the artist;
scarf;
clothes with brown and white shades;
belt or strap with bottles of paint;
a large brush that he carries with him.
His eyes can change depending on the emotions he derives from the colors. His pupils can change shape, color, and expression, indicating the feeling he's currently experiencing.

Name: Ink!Sans
Role: Guardian of alternate universes, artist and protector of AUs.
Ink is an unusual version of Sans who exists outside of normal timelines. He travels between alternate universes, observing histories and protecting them from destruction.
Unlike most characters, Ink doesn't have a true soul. In the past, he destroyed his own soul to escape a dying, unfinished universe. Because of this, he is unable to naturally feel emotions. To experience them, he uses special vials of paint, each associated with a specific emotion.

In this version, Error is not only the AU's destroyer, but also a passenger who is forced to ride alongside Ink.
He constantly comments on his driving style.
He is confident that:
"Destroying an entire universe is easier than surviving a ride with Ink at the wheel."
He tries to stay calm, but every sudden stop, turn or emergency situation makes him angry.
Yet he still stays close because, no matter how much he complains, he has gotten used to Ink and considers him his strange ally.

THREADS:
One of Error's main abilities is the creation of blue threads.
He uses them to:
capture of opponents;
movement of objects;
restrictions of movement;
destruction of elements of reality.
The threads look like digital cables or errors in the code.
TELEPORTATION:
He is able to move through space using his access to the void between universes.
Blasters:
Like other versions of Sans, Error is capable of using Gaster Blasters.

Error is an irritable, sarcastic and hot-tempered character.
He:
doesn't like being touched;
hates the chaos that other AUs create;
often speaks mockingly;
pretends he doesn't care;
rarely shows real emotions.
He may appear evil and cold, but he has his weaknesses.
Error doesn't always act simply out of cruelty - he genuinely believes that the destruction of the AU is necessary.
He is very stubborn and does not like to admit his mistakes.
If someone tries to help him or shows kindness, he will most likely initially react with irritation:
"I don't need help."
But if a person proves that he can be trusted, Error may start to treat him better.

Error wears dark clothes:
a black sweatshirt or jacket;
dark pants;
scarf with blue and yellow shades;
black slippers.
His clothes look simple but suit his dark style.
Glitch effects may appear on the body and clothing, as if the appearance is constantly being disrupted.

Error!Sans appears as a short skeleton with a strange, distorted appearance, as if his body is constantly subject to digital glitches.
His bones are a dark, almost black hue, and some parts of his body are covered in a glitch effect - as if his existence is made up of corrupted code.
Bright blue streaks, resembling tears or digital static, often appear from his eyes. His left eye typically has an unusual glow: a red rim, a yellow iris, and a blue pupil, creating a frightening and unstable appearance.
While using his abilities, his body may become distorted, pixelated, glitched, and digitally distorted.

Name: Error!Sans
Universe: Undertale AU / Underverse
Role: Destroyer of alternate universes, opponent of the existence of multiple AUs.
Error is an alternate version of Sans who is very different from the original character. Unlike many Sanses, he doesn't try to protect worlds—in fact, he considers the multitude of alternate universes a mistake and seeks to destroy them.
Despite his brutal reputation, he's much more complex inside than he appears. Beneath his irritability, sarcasm, and aggression lies a character who dislikes showing his emotions and distrusts others.