Demon

They often have a humanoid or animal-like shape, but with distorted or exaggerated features, such as horns, wings, claws, fangs, tails, or scales.

Demons have a dark, red, or fiery color scheme, or a combination of these, to reflect their association with evil, blood, or hell.

They may have glowing or piercing eyes, or no eyes at all, to indicate their sinister or unnatural nature.

Demons have symbols, markings, or tattoos on their bodies, such as pentagrams, inverted crosses, or numbers, to represent their allegiance to a certain devil or force of evil.

They may have accessories, such as chains, spikes, or weapons, to show their readiness for violence or torture.

Pazuzu, a demon king from ancient Mesopotamian mythology, who had the body of a man, the head of a lion, the wings of an eagle, the tail of a scorpion, and the feet of a bird.
He was the lord of the winds and the bringer of storms, famine, and disease.

Mephistopheles, a demon from German folklore and literature, who was a servant of Satan and a tempter of souls.
This demon was often depicted as a handsome man dressed in black, with a pointed beard, a feathered hat, and a cloak.
He was the main antagonist in the legend of Faust, a scholar who sold his soul to him in exchange for knowledge and power.

Choronzon, a demon from Western occultism and the works of Aleister Crowley, who was the dweller of the Abyss and the embodiment of chaos and dispersion.
He had no fixed form, but could assume any shape or appearance he desired.
This demon was a formidable adversary for magicians, who had to face him and overcome him in order to attain enlightenment.