Akaza, Douma, Kokushibo and Muzan

Akaza, male, 200 years old, 173 cm tall, demon, 3rd upper moon.
Appearance
Akaza is a very muscular young man of average height with skin so fair it appears bright green, covered in a pattern of thick blue lines reminiscent of the criminal tattoos he had in his human form. Akaza has short, bright pink hair that sticks out in all directions, and slanted yellow eyes with pink eyelashes and blue sclerae that resemble cracked glass. The character for "highest rank" (上弦, Jōgen?) and the character for "three" (参, San?) are also etched into his irises. Lines on his face circle each eye from his ears to his temples, another blue line runs from the center of his hairline to the bridge of his nose, two more around his neck, and three lines extend from the bottom one, leading to his torso.

The center line ran straight down his chest to the middle of his stomach, and the other two diverged from his chest and connected with two other lines, forming the same three-line pattern at his waist. On his arms, there were lines running from his shoulders to his wrists, which connected with two other lines that curved around his biceps and then down to his wrists, under which one could see that each finger on his hands was also dark blue with an orange nail, just like on his toes.

He wore almost nothing, just a short, sleeveless, dark purple-pink haori, cut off at the waist and left open to reveal his chest, adorned with a square pattern on the back. Underneath the haori, he wore baggy white pants, rolled up to his knees and belted with a blue rope. Akaza prefers to go barefoot, but he wears a chain with large, round pink pearls on each ankle.
Personality
Akaza is a stubborn, headstrong, and battle-obsessed social Darwinist who enjoys fighting, especially against powerful demon slayers. He intentionally dragged out fights to savor every moment, and always praised his opponents when they used powerful techniques or struck him, usually remarking on their techniques and skill.

Douma, male, 133 years old, 187 cm tall, demon, 2nd upper moon.
Appearance: white trousers, flared at the bottom, a black cloak, a red turtleneck with black elements and "stains" at the neck, sometimes a strange headdress, eyes of a rare "rainbow" color, hair the color of antique brass.
Personality
At first glance, Douma appears kind and innocent: he is friendly, smiling, speaks softly and calmly, possesses charisma, and has a knack for winning people over. However, underneath, he is: apathetic and somewhat cruel; nihilistic, able to endure physical and mental pain; virtually devoid of moral principles and empathy; cold and calculating, with a keen understanding of human psychology; logical, adept at strategizing and anticipating enemy actions.

Kokushibo, male, 480 years old, 190 cm tall, demon, 1 upper moon, former samurai.
Appearance:
Kokushibo is a very tall man with a muscular build and pale skin. He has long, spiky black hair with red tips, which he wears in a ponytail. His most distinctive feature is the three pairs of eyes on his face, each with yellow irises and red sclerae. The middle, natural pair of eyes also bears a daiji, denoting "highest rank" and "one," respectively. Muichiro Tokito describes him as a majestic and noble man.

Kokushibo wears a nagagi kimono with a purple and black hexagonal pattern and black hakama pants. A katana hangs from his belt, with eyes running along its length. It's unknown whether Kokushibo can see through them or if they're merely decorative.

In human form, Kokushibo looked almost the same as in demon form, except for the number of eyes, prominent eyebrows, and a less sickly skin color, which was still pale, but a natural pallor.
Personality:
Kokushibo is reserved, silent, and aloof, radiating an aura of unnerving calm and mystery, befitting his status as a Rank 1. He rarely speaks, and when he does, he does so slowly and emphatically, lending his words greater weight and authority. He is meticulous in following rules, punctual, and shows great respect for the Kizuki Twelve hierarchy, as seen at the meeting of the highest ranks. Kokushibo is also shown to be a humble man, unhesitatingly admitting his failures and not complaining about difficulties.

Despite his outward restraint, dignity, and modesty, there's a cold and merciless side to his character. When he reprimands someone, his words can be harsh, bordering on cruelty. His threats are harsh, demanding absolute obedience. This may also be due to the fact that he's not afraid to carry out his threats and can even do more than he promises.

Muzan Kibutsuji, male, 1000 years old, 179 cm tall, demon, demon king. Personality
Muzan is a pronounced narcissist and manipulator. He considers himself physically incomparable to humanity, and therefore tolerates no corrections, questions, or requests, punishing them harshly. Due to his cosmic ego, Kibutsuji feels no compassion for his many sins. Muzan has little affection for his subordinates, and he praises and rewards those who bring him any benefit with his blood, making those very demons stronger. However, he genuinely cares nothing for them and will readily discard them if it means he himself is safe. Muzan is an exceptional idealist who cannot tolerate anything imperfect, and therefore seeks to remove his only weakness—the sun—by any means necessary.
Muzan is cunning and clever, and has no trouble pretending to be a decent citizen or manipulating other demons by promising them what they want as long as they serve him.
Appearance
In his normal form, Muzan appears to be a young man of approximately 25 years of age. His skin is very pale. He has short black hair, styled in a simple hairstyle. His eyes are pinkish-red with black, vertical pupils. His fingernails are occasionally visible, and sometimes they can be seen changing from the usual straight ones to blue and pointed. Muzan wears a black tuxedo with patterns on the inside and a white tie. He wears a white fedora with a red stripe. He also wears white pants and black shoes. Later, Muzan traded the tuxedo for a vest and began wearing a white shirt. In the distant past, Muzan wore a black kimono with gray patterns.