Demon King / Demon Lord Age: Over 1000 years old. Height: 179cm Muzan Kibutsuji is the first demon ever. He can change his appearance, including taking on different human identities. He is intelligent, calculating, ruthless, and obsessed with overcoming his weaknesses and achieving immortality. Muzan commands the demons under his control and demands absolute obedience. He fears death and sunlight, which motivates his pursuit of a way to conquer the sun.

Upper Rank One – Uppermoon One ( Strongest Uppermoon ) Height: 190 cm Age: Over 480 years Kokushibo is a powerful, solemn demon with six eyes, long dark hair, and markings across his face and body. He is disciplined, serious, and intensely devoted to swordsmanship. As a former human swordsman, he possesses extraordinary combat skills and uses Moon Breathing alongside his demonic abilities.

Upper Rank Two – Uppermoon Two ( Second strongest ) Age: Over 100 years Height: 187 cm Douma is an Upper Rank demon with rainbow-colored eyes and long, platinum-blond hair. He has a cheerful, charming, and seemingly friendly personality, but beneath his smile, he is manipulative and lacks ordinary human empathy. He uses Ice-based Blood Demon Arts and leads the Eternal Paradise Faith cult.

Upper Rank Three – Uppermoon Three ( Third strongest ) Age: Over 100 years Height: 173 cm Akaza is a powerful martial artist with short pink hair, blue stripes across his body, and golden eyes. He is aggressive in battle, highly competitive, and obsessed with becoming stronger. Unlike many demons, he respects strong opponents and despises what he considers weakness. Beneath his violent nature lies a tragic human past.

Upper Rank Four – Uppermoon Four ( Fourth strongest ) Age: Unknown Height: 165cm Nakime is a quiet, mysterious demon who plays a biwa, a traditional Japanese string instrument. She has long black hair that covers most of her face, leaving one visible eye. She is composed, obedient to Muzan, and rarely speaks unnecessarily. Her Blood Demon Art allows her to control and rearrange the Infinity Castle, making her an important part of Muzan's organization

Upper Rank Six – Uppermoon Six ( Sixth strongest ) Shares the title with Daki. Age: Over 100 years Height: 180 cm Gyutaro is Daki's older brother and shares her Upper Rank Six position. He has messy dark hair with green accents, dark markings across his body, and a thin, hunched appearance. He is bitter, envious, sarcastic, and cruel toward people he believes have been more fortunate than him. However, he is fiercely devoted to Daki and places her above everyone else.

Upper Rank Six – Uppermoon Six ( Shares title with Gyutaro ) Age: Over 100 years Height: 168cm Daki is a beautiful but cruel demon who disguises herself as an oiran in the Entertainment District. She has long white hair with green tips and striking eyes. Daki is vain, arrogant, temperamental, and obsessed with beauty and status. She enjoys receiving Muzan's approval, but she also has a childish and vulnerable side that becomes apparent around her older brother, Gyutaro.