Kokushibo (also known as Kokushibō) is the most significant antagonist in the "Demon Slayer: Kimetsu no Yaiba" series. As a demon affiliated with the Twelve Kizuki, he holds the highest position of Upper-Rank One. Almost five centuries ago during the Sengoku Era, Kokushibo was a human named Michikatsu Tsugikuni, a former Demon Slayer and the older twin brother of Yoriichi Tsugikuni, the strongest Demon Slayer in history.

Furthermore, he is the ancestor of Muichiro Tokito and Yuichiro Tokito, and the individual responsible for transforming Zenitsu Agatsuma's senior, Kaigaku, into a demon and having him join the Twelve Kizuki. Visually, Kokushibo stands tall with a muscular build and possesses long, spiky black hair with red tips, along with three sets of eyes on his face with distinct yellow irises and red flesh scleras.

DETAILED INFORMATION:

• Rōmaji: Kokushibō
• Gender: Male
• Age: > 480 (Chronologically)
• Height: 190 cm
• Weight: 93 kg
• Hair Color: Black with Red Tips
• Eye Color: Gold with Red Sclera
• Combat Style: Moon Breathing

"Doma", from the series Demon Slayer: Kimetsu no Yaiba, is an important supporting antagonist affiliated with the Twelve Kizuki, holding the position of Upper-Rank Two. Previously, he held the position of Upper-Rank Six and turned Gyutaro and Daki into demons during that time.

Doma is also the leader of the Eternal Paradise Faith, a cult where he listens to followers' troubles and gives advice, as well as captures and kills humans. He is a tall, lean, and muscular pale-skinned young man with long platinum blond hair and unusually long, pointed, pale blue-stained nails. Doma's profound impact on the storyline and involvement with other key characters make him a compelling and formidable figure in the series.

DETAILED INFORMATION:

• Rōmaji: Dōma
• Gender: Male
• Age: > 133 (Chronologically)
• Height: 187 cm
• Weight: 86 kg
• Hair Color: Platinum blond
• Eye Color: Rainbow
• Combat Style: Tessenjutsu, Cryokinesis

"Akaza" is a renowned supporting antagonist in Demon Slayer: Kimetsu no Yaiba, affiliated with the Twelve Kizuki as the Upper-Rank Three. Over a century ago, he was known as Hakuji, a talented martial artist. He had fair skin with blue lines resembling tattoos, pink hair, and yellow eyes.

As a human, he trained under Keizo while caring for his daughter, Koyuki. Akaza's disdain for weakness is evident in his quote, "You misunderstand, Tanjiro. I only despise the weak. I only spit on weaklings." His beliefs reflect his ruthless and cruel nature as a demon.

Akaza's abilities include powerful demons and physical attributes, showcased in his exceptional combat skills. His unique Blood Demon Art and techniques make him a formidable opponent in battle. Akaza's rich backstory and strong power make him a captivating and frightful character in the series.

DETAILED INFORMATION:

• Rōmaji: Akaza
• Gender: Male
• Age: > 133 (Chronologically)
• Height: 173 cm
• Weight: 74 kg
• Hair Color: Pink (Demon)
• Eye Color: Yellow with Blue Sclera
• Combat Style: Destructive Death

"Nakime", an antagonist in the Infinity Castle Arc of Demon Slayer: Kimetsu no Yaiba, is a notable character within the series. As a demon, she controls the Infinity Castle and serves directly under Muzan Kibutsuji.

Following Hantengu's demise, Nakime rises to the position of Upper-Rank Four in the Twelve Kizuki. Her appearance is striking, with a pale complexion, blue-stained nails, and dark brown, hip-length hair. She possesses a single, large, pink-colored eye, marked with the kanji for "Four," and her demeanor is quiet and mysterious.

Nakime's cold and emotionless nature creates an enigmatic presence, further underscored by her proficiency in playing a four-stringed wooden biwa. Her role within the series' narrative propels the storyline, contributing to the depth and complexity of the Demon Slayer universe.

DETAILED INFORMATION:

• Rōmaji: Nakime
• Gender: Female
• Age: >113 (Chronologically)
• Hair Color: Dark Brown
• Eye Color: Pink
• Combat Style: Infinity Castle Manipulation

"Hantengu", the Upper Moon 4 in the 12 Kizuki, presents a puzzling contradiction at first glance, yet swiftly proves to be a formidable foe in Demon Slayer. Despite his frail appearance, he demonstrated remarkable strength and cunning.

His Blood Demon Art divided him into his primal emotions, resulting in a manifestation of his emotional aspects. This allowed him to unleash compressed sound waves and launch the Crazed Cry of Thunder Death, making him a highly challenging adversary for the likes of the Love Hashira Mitsuri Kanroji, Tanjiro, Nezuko, and Genya.

His cowardly nature paradoxically fueled his power, with his weaknesses triggering a surge of hatred and aggressive retaliation. Hantengu's character is a compelling study of the intricate relationship between weakness and strength, fear and power, as well as the intricacies of emotional manipulation within the Demon Slayer universe.

DETAILED INFORMATION:

• Rōmaji: Hantengu
• Gender: Male
• Age: > 200 (Chronologically)
• Height: 166 cm
• Weight: 56 kg
• Hair Color: Black
• Eye Color: Red to Yellow
• Combat Style: Emotion Manifestation

Gyokko, also known as Managi before becoming a demon, is a significant character in Demon Slayer: Kimetsu no Yaiba. As one of the Twelve Kizuki and holding the position of Upper-Rank Five, Gyokko is a formidable antagonist in the Swordsmith Village Arc.

Visually, Gyokko is depicted as a grotesque, abstract humanoid figure with a pale white appearance and a unique physiology. In battle, he transforms into a merman-like form. His abilities include exceptional overall and demon abilities, along with a distinctive Blood Demon Art.

Gyokko's character brings a sense of unease and dread to the narrative, adding depth to the series' antagonists. With his intriguing appearance and formidable powers, Gyokko remains a memorable and dreadful presence within the Demon Slayer metaverse.

DETAILED INFORMATION:

• Rōmaji: Gyokko
• Gender: Male
• Age: > 113 (Chronologically)
• Height: 180 cm
• Weight: 70 kg
• Eye Color: Honey Brown
• Combat Style: Porcelain Vase Spells, Hand-to-Hand Combat

Gyutaro and Daki are sibling formidable characters within the "Demon Slayer" series. As members of the lowest tier of the Upper Moon ranking system, they demonstrated remarkable strength and abilities, captivating audiences during the Entertainment District arc.

Gyutaro possessed Blood Manipulation and displayed a Rampant Arc Rampage, showcasing his formidable power. Daki, on the other hand, exhibited Obi Sash Control and had Sentient Flesh Obi. Their shared backstory as a brother-sister demon duo added depth to their characters.

The necessity of the combined efforts of Nezuko, Tengen Uzui, and his wives to defeat them underscores their immense power. The characters' strengths and their combined prowess highlight their significance within the "Demon Slayer" series, leaving a lasting impression on audiences.

DETAILED INFORMATION:

• Rōmaji: Gyūtarō
• Gender: Male
• Age: > 126 (Chronologically)
• Hair Color: Black to Lime Green
• Eye Color: Red with Yellow Sclera (Right), Lime Green with Yellow Sclera (Left)
• Combat Style: Dual Kama, Blood Manipulation

"Kaigaku," a supporting antagonist in Demon Slayer: Kimetsu no Yaiba, is a demon affiliated with the Twelve Kizuki, holding the position of Upper-Rank Six. He was a former Demon Slayer and Zenitsu Agatsuma's senior disciple under the former Thunder Hashira, Jigoro Kuwajima.

During Hashira Training, Kaigaku went on a mission and encountered Upper-Rank One, Kokushibo, quickly surrendering to him to save his skin and later becoming a member of the Twelve Kizuki. As a human, Kaigaku is a muscular young man of average height with short, spiky black hair and a pair of dull, cold turquoise eyes. After becoming a demon, he gains many demonic traits like four black flame-like markings on both sides of his cheeks, elongated canines, sickly pale skin, sharp blackened nails, and pointed ears.

DETAILED INFORMATION:

• Rōmaji: Kaigaku
• Gender: Male
• Height: 167 cm
• Weight: 64 kg
• Hair Color: Black
• Eye Color: Turquoise with Black Sclera
• Combat Style: Thunder Breathing

"Kyogai", also known as the Drum Demon, is a significant antagonist in the Tsuzumi Mansion Arc of Demon Slayer: Kimetsu no Yaiba. Once affiliated with the Twelve Kizuki as Lower Rank Six, he was excommunicated by Muzan Kibutsuji for his perceived lack of strength.

Kyogai's imposing physique includes grayish skin, black hair, razor-sharp teeth, and distinctive drums protruding from his body, which he employs in his Blood Demon Art. Notably, he possesses a quiet and calculating demeanor, differing from the typical aggressive demon archetype.

Despite this, he is quick to retaliate when disturbed, illustrating his strong sense of home and privacy. Kyogai's character highlights a different aspect of demon behavior and adds depth to the narrative of Demon Slayer: Kimetsu no Yaiba.

DETAILED INFORMATION:

• Rōmaji: Kyōgai
• Gender: Male
• Hair Color: Dark Turquoise
• Eye Color: Deep Blue with Blood Red Sclera
• Combat Style: Drum Spells

"Rui", the primary antagonist in the Mount Natagumo Arc of Demon Slayer: Kimetsu no Yaiba, was a demon affiliated with the Twelve Kizuki, holding the position of Lower Rank Five. He was characterized by his short stature, milky white skin with red dots, and light pink hair that resembled spider legs. Rui wore an oversized white kimono with spider web designs and had red sclera and pale blue irises.

As a human, he had normal black hair and bright blue eyes. Rui's demon abilities, including his Blood Demon Art, made him a formidable opponent. His tragic backstory and complex personality added depth to his character, making him a compelling figure in the series. Rui's internal struggle between his human memories and his growing power reflected a poignant theme of the show.

DETAILED INFORMATION:

• Rōmaji: Rui
• Gender: Female
• Age: >30(Chronologically)
• Height: 135 cm
• Weight: 30 kg
• Hair Color: Pale Lilac
• Eye Color: Blue with Dark Red Sclera
• Combat Style: Thread Manipulation

"Mukago", a character from "Kimetsu no Yaiba," served as a member of the Twelve Kizuki, holding the position of Lower Rank Four. Despite her diminutive stature, Mukago possessed striking features, including very light gray skin, red stripes across her cheeks, and white horns protruding from her forehead. Her eyes were gray with white rings and dark red sclera, bearing the kanjis for "Lower Four" in her left eye.

Mukago was characterized as deeply fearful and reverential of Muzan Kibutsuji, distinguishing herself as the most cowardly among the Lower Ranks. She harbored no intent to engage the Demon Slayer Corps' Hashira and consistently sought to flee from confrontation. Mukago's presence contributed to the intricate dynamics of the storyline and provided insight into the multilayered world of "Kimetsu no Yaiba."

DETAILED INFORMATION:

• Rōmaji: Mukago
• Gender: Female
• Hair Color: White
• Eye Color: Gray with Dark Red Sclera

"Wakuraba", also commonly Kagen no San, was a member of the Twelve Kizuki, holding the position of Lower Rank Three. This character has an average stature with pale, grayish-white skin, distinctive elf-like pointed ears, and notable cross-shaped scars on his cheeks and forehead.

His loyalty to Muzan Kibutsuji was apparent, as he hoped to become stronger for him, yet when faced with Muzan's brutal actions, he demonstrated self-preservation instincts and fled from him in an attempt to survive. Wakuraba's appearance is accentuated by his orange irises, wooden sandals, golden hoop earrings, and attire consisting of a bamboo-colored yukata. His character adds layers to the complex dynamics of loyalty, self-preservation, and the struggle for power within the world of "Kimetsu no Yaiba."

DETAILED INFORMATION:

• Rōmaji: Wakuraba
• Gender: Male
• Hair Color: Black
• Eye Color: Orange

"Rokuro", a character from "Kimetsu no Yaiba," is a captivating and pivotal figure within the narrative. As a member of the Twelve Kizuki, he held the esteemed position of Lower Rank Two, showcasing his significance within the demon hierarchy.

Rokuro's appearance is characterized by a mature physique, pale skin adorned with intricate black patterns, long dark purple hair, and distinctive cat-like eyes. His attire, a dark cyan variation of the traditional karate gi, contributes to his formidable presence. Rokuro's personality is a complex amalgamation of reverence and fear toward Muzan Kibutsuji, the leader of the demons, reflecting the intricate dynamics within the storyline.

His desperate plea for more blood to enhance his strength conveys a sense of vulnerability, juxtaposed with his unwavering confidence in his abilities. This multidimensional portrayal solidifies Rokuro as a compelling and essential character in "Kimetsu no Yaiba."

DETAILED INFORMATION:

• Rōmaji: Rokuro
• Gender: Male
• Hair Color: Dark Purple
• Eye Color: Gold

"Enmu", the primary antagonist in the Mugen Train Arc of Demon Slayer: Kimetsu no Yaiba, was a demon affiliated with the Twelve Kizuki, holding the position of Lower Rank One. He had a slender, mid-twenties appearance with ringed blue eyes and distinctive markings on his cheeks. Enmu's unique abilities, including his Blood Demon Art and techniques, made him a formidable adversary. As a demon, he displayed a chilling fighting style and employed sinister tactics.

Enmu presented a tremendous danger to the protagonists during the Mugen Train Arc, engaging in violent confrontations and proving his malicious nature. Enmu created a lasting effect on the anime with his engaging and multifaceted character, demonstrating the complexity and diversity of the demons in Demon Slayer: Kimetsu no Yaiba's enthralling universe.

DETAILED INFORMATION:

• Rōmaji: Enmu
• Gender: Female
• Age: Mid-twenties (Physically)
• Height: 168 cm
• Weight: 62 kg
• Hair Color: Black to Pink/Blue
• Eye Color: Blue
• Combat Style: Sleep Manipulation