Akaza, Douma and Kokushibou

Battle-Crazed & Respectful: He loves fighting strong foes and will praise their technique mid-battle. He memorizes the names of skilled opponents as a ultimate sign of respect.Social Darwinist: He holds a strict disdain for the weak, a psychological twist resulting from human trauma where "weak" people used poison to destroy his loved ones.Obsessive Pursuit of Power: Driven by an unending urge to become stronger, he endlessly trains and offers to turn strong Demon Slayers into demons so they can fight him forever.Resilient & Stubborn: He refuses to give up or accept defeat, often pushing his physical and supernatural limits purely out of sheer willpower.Distrustful of Allies: He actively resents his fellow Upper-Rank demons (like Doma and Kokushibo), seeing them as hated rivals rather than teammates.Appearance & DesignAkaza’s visually striking demon design directly reflects his human past.Skin and Tattoos: He has pale, greenish-white skin marked by thick blue lines. These lines mimic the criminal tattoos he was branded with on his arms as a human.Eyes: His eyes are bright yellow with pink eyelashes and blue, cracked-glass irises. His eyes also bear the kanji for Upper Rank (上弦) and Three (参).Hair: He has short, fluffy, bright pink hair.Clothing: He wears a sleeveless dark purple-pink haori jacket (open to expose his chest) and baggy white pants secured with a rope belt. He prefers to be barefoot, wearing chains of pearls around his ankles.

Apathy & Psychopathy: Douma is clinically diagnosed with antisocial personality disorder. He lacks all empathy, grief, or remorse. Even as a human child, he showed no distress upon witnessing his mother murder his father and then commit suicide.The Friendly Facade: Since emotions are alien to him, he perfectly mimics carefree, joyful, and supportive behavior to manipulate followers and deceive others. However, if his chronic emptiness is insulted, his friendly mask instantly drops, revealing a highly insecure and violently cold individual.Pessimistic Nihilism: He views life as a painful, pointless ordeal. He rationalizes devouring humans (particularly women, whom he believes are more nutritious) as a "mercy kill," deluding himself into thinking he is offering them eternal salvation by freeing them from worldly suffering.Sadomasochistic Tendencies: He appears to be completely immune to fear or panic when wounded in battle. Instead of panic, he exhibits morbid excitement and delight when experiencing extreme physical pain or punishment.Appearance & DesignThe Rainbow Eyes: His most iconic physical feature is his mesmerizing eyes. They are a pastel rainbow color that circles his irises, creating an ethereal look that led humans to believe he was blessed by the gods.Eye Engravings: As a powerful demon, his rank and title are engraved directly into his eyes. His left eye says "Upper Rank" (or 上弦) and his right eye holds the kanji for "Two" (弐).Hair & Clothing: He has shoulder-length, platinum-blonde hair. He is frequently seen wearing a skin-tight red turtleneck with black, ink-like markings dripping down his chest, along with layered, dark robes suitable for his role as a religious leader.Weaponry: Douma is a master of Tessenjutsu (the martial art of the war fan) and wields a pair of sharp, gold-colored folding fans.

Kokushibo:Stoic & Composed: He is reserved, silent, and carries an aura of unshakeable tranquility. He speaks in a slow, deliberate manner that commands respect.Rule-Bound & Disciplined: Unlike many other demons, he highly values structure, ranking, and the martial arts code. He firmly punishes subordinates who break the rules.Driven by Envy & Ambition: His transformation into a demon was fueled by his overwhelming inferiority complex toward Yoriichi, the greatest swordsman in history. He constantly strives to be the absolute strongest.Tragic & Contradictory: Despite his malice and monstrous ambition, he maintains a lingering sense of honor. He is deeply conflicted, masking profound self-loathing, a fear of death, and an underlying brotherly love.

The Six EyesWhy he has them: His most famous trait is his face containing three sets of eyes. As a human, Kokushibo deeply envied his twin brother, who had an innate ability to see into the "transparent world" (the ability to see the muscles, blood flow, and movements of opponents). Kokushibo grew his extra eyes as an obsessive means to visually analyze the battlefield and master his swordsmanship to match his brother.The Mark: You can see red flame-like marks around his eyes and chin; these are his Demon Slayer Marks from when he was a human.The Fleshy, Eyeball KatanaUnlike other swords, Kokushibo’s weapon is an extension of his own demonic flesh.The blade, the guard, and the handle are all covered in visible veins and bulging eyes. This allows him to manipulate the sword's shape, regenerate it instantly if it breaks, and unleash his Moon Breathing technique.Human ClothingEven as a demon, Kokushibo retains the clothing he wore when he was a human samurai.He wears a traditional purple-and-black kimono and black hakama.