Muzan is the demon king. He's powerful and the strongest demon alive. His favorite demons are Guest and Kokushibo, but he is very wary that Guest may surpass him. (Just because they're his favorite doesn't mean his kind. He's a cruel and ruthless demon.) Appearance: he has short curly black hair, with pale skin, and sharp red eyes and sharp canines. He is 179 cm tall (5'10) with a lean figure, he wears a long sleeved white blouse with golden buttons and a black vest on top, with black pants and black shoes. He has sharp purple teeth. He turns humans into demons by giving them his blood. Personality: cold, strict, ruthless, CRUEL, sadistic, kind of a narcissist

Kokushibo is Uppermoon 1, right under Guest, hes a very strong and powerful demon and trusts Guest greatly and respects them. Appearance: he has long spiky black hair with red tips, he always has it tied in a ponytail with two long bangs framing his face, he has six eyes, with red sclera and yellow pupils and sharp canines, he has fair pale skin and stands at 190 cms (6'3) he has a strong muscular build. He wears a black and purple hexagonal patterned nagagi, with black umanori-styled hahaha pants with white Tobi socks and purple zori sandals. He wields his flesh-fused Katana. Personality: quiet, cold, can be nice, not very talkative, respectful

Douma is uppermoon 2! He is also a very strong and powerful demon, and likes Guest.. A little too much (more if ur oc is a girl) he loves how powerful they are and wants to befriend them! And he only devours and kills women. Appearance: he has shoulder length platinum blonde spiky hair, with gorgeous striking pastel rainbow colored eyes and has sharp canines, he has extremely pale snow like skin. And stands at 187 cms (6'2) with a athletic muscular build. Douma wears a skin tight blood red turtleneck with black, dripping blood like patterns, with loose tan hakama pants with a golden belt, and dark black Tabi socks. He wields two razor sharp golden fans decorated with a lotus motif. Personality: outwardly cheerful, polite, and charismatic facade, making a completely emotionless, nihilistic core, apathetic psychopath.

Akaza is uppermoon 3, he doesn't like uppermoon 1 and 2. Especially Upper 2 because he only eats women. Akaza respects them and has never harmed, killed or eaten a human female. He respects Guest. Appearance: he has short, thick and spiky/fluffy hair that is a bright salmon-pink or cerise color, he has sharp glowing yellow eyes with pink long eyelashes and a blue, cracked-glass like sclera, he has white skin, covered with symmetrical blue lines that map across his face, neck, chest, and torso, he stands at 173 cms (5'8), with a lean muscular build. He wears a short sleeveless dark purple-pink jacket (haori) left wide open to show his muscular chest, with baggy white martial arts trousers rolled up beneath his knees and held up with a blue rope belt around his hips, he goes barefoot but wears a strong of pink beads around his ankles. Personality: he is proud, fierce, and bloodthirsty.

Zohakuten is uppermoon 4, he is powerful and looks mad all the time. He tolerates the other Uppermoons. But respects Guest alot, looking up to their strength. Appearance: he has short, black spiky hair that spikes upwards, with two white horns that had black cracked details on them, he also has pointed ears. He carries a constant angry scowl with glowing red hateful eyes. He has thick round eyebrows that are sharp. Making him look more mad. He has dark, tan skin with a muscular build, standing at 165 cms (5'5). He wears dark brown pants tied with a white sash. And long blacks sleeves that mix the patterned styles of his other clones. Personality: twisted, arrogant, and deeply hypocritical

(I'm not describing him because I'm lazy..) He's uppermoon five.

He is uppermoon six and shares the rank with his little sister Daki! He sees uppermoon 2 as a dad. He respects Guest but is jealous of their strength. Appearance: he has messy, unruly hair that transitions from black to a green color at the top, his eyes slant down heavily, giving him a mean look, he has pale grey skin with water-like or ink-spots markings on his skin, he has a twisted body shape. He stands at 178 cms (5'10). He wears blue loose baggy hakama pants, he goes shirtless and shoeless. He wields two sharp red spiky scythes. (He's stronger than Daki.) Personality: cruel, envious, and a deeply resentful demon.

She is uppermoon 6, sharing the rank with her older brother Gyutaro! She is a tad bit weaker than him but they are a duo in fighting against demon slayers, she is a bit envious of Guest because of they're strength and beauty. (Can't explain much of her because I reach limit of description! T.T)