KRD and BSD

Tanjiro Kamado is a selfless young man who became a fighter to restore his sister's human form. He uses the Breath of Water and Hinokami Kagura (Sun Breath).
Nezuko Kamado is Tanjiro's younger sister, transformed into a demon but retaining her human feelings. She protects people and can change her size.
Zenitsu Agatsuma is a cowardly but incredibly gifted swordsman. He only fights at full strength when he faints from fear. He wields the Breath of Thunder.
Inosuke Hasibira is an eccentric fighter raised in the mountains. He wears a boar mask, uses a homemade Beast Breath, and wields twin serrated blades.
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Pillars (Highest Rank of Fighters)
Giyu Tomioka (Water Pillar) is a silent and aloof swordsman who spared Nezuko and sent Tanjiro to train.
Shinobu Kocho (Insect Pillar) - uses poisons from wisteria, as he does not have enough physical strength to decapitate a demon.
Kyojiro Rengoku (Flame Pillar) is a cheerful, noble, and incredibly strong-willed warrior who died in the battle on the Infinity Train.
Tengen Uzui (Sound Pillar) is a former ninja (shinobi) with a penchant for flamboyance and outrageous behavior. He has three wives and assistants.
Muichiro Tokito (Mist Pillar) is a 14-year-old prodigy who became a Pillar after just two months of training. Initially, he suffered from amnesia.
Mitsuri Kanroji (Pillar of Love) is an incredibly strong girl with a flexible ribbon sword who is looking for a worthy husband in her service.
Obanai Iguro (Snake Pillar) is a stern and secretive fighter with a snake around his neck who is secretly in love with Mitsuri.
Sanemi Shinazugawa (Wind Pillar) is a scarred, rough, and hot-tempered man who possesses a rare blood that intoxicates demons.
Gyomei Himejima (Stone Pillar) is the strongest of the Pillars. A blind, giant monk who wields a chained axe and a spiked mace in battle.
Main antagonists
Muzan Kibutsuji is an original demon and the leader of the Twelve Demon Moons, capable of changing appearance and mercilessly executing his subordinates for failure.
Kokushibo (First Upper Moon) —
‎xz six-eyed demon swordsman, former fighter and older brother of Yoriichi.
Douma (Second Upper Moon) is a charismatic, yet completely emotionless, psychopath who leads a cult.
Akaza (Upper Moon 3) is a master of hand-to-hand combat who values ​​only strength and despises the weak.
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Armed Detective Agency (ADA)
An organization of espers that investigates crimes that the police cannot handle.
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Atsushi Nakajima is the main character, an orphan with a kind heart and low self-esteem. His "Moonlit Beast" ability allows him to transform into a white tiger with high regeneration.
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Wikipedia
Osamu Dazai is the former head of the Port Mafia, a brilliant strategist, and an eccentric detective with suicidal tendencies. His "Incomplete Human" ability nullifies any other person's powers upon contact.
Doppo Kunikida is Dazai's strict, idealistic partner, obsessed with planning and notebooks. His ability, "Doppo's Poetry," materializes any notebook-sized object by writing its name on it.
Rampo Edogawa is the agency's top detective, a childish but unrivaled genius. His "Super Deduction" skill instantly solves any crime; Rampo believes it's magic, though in reality, he's just an ordinary man.
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Akiko Yosano is the agency's staff doctor, with a sadistic streak during treatment. Her ability, "Don't Give Up Your Life, My Love," completely heals any wound, but only works if the patient is on the brink of death.
Kyouka Izumi is a former mafia mercenary rescued by Atsushi. Her "Snow Demon" ability materializes a phantom swordsman who initially obeyed only orders from a telephone receiver.
Port Mafia
An underground syndicate organization that controls the shadowy life of Yokohama.
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Ryunosuke Akutagawa is a ruthless mafioso who craves the recognition of his former mentor, Dazai. His Rashomon ability transforms his cloak into a dark, all-consuming substance capable of cutting through even space.
Chuuya Nakahara is a hot-tempered mafia executive and Dazai's former partner in the Double Black duo. His ability, "Vague Sadness," allows him to completely manipulate the gravity of any object he touches.
Ougai Mori is the leader of the Port Mafia, a former military doctor, a calculating and pragmatic leader. His "Vita Sexualis" ability materializes an esper girl named Alice, who carries out his will without question.
Main antagonists
Characters from outside groups who oppose the agency and the mafia.
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Fyodor Dostoevsky is the leader of the "Rats of the Dead House" and a member of the "Death of the Celestials," a religious fanatic who wants to cleanse the world of espers. His "Crime and Punishment" ability can instantly kill a person with a single touch (it has hidden rules).
Francis Scott Fitzgerald is the former leader of the American Guild. His "Great Gatsby" ability increases his physical strength proportionally to the amount of money he spends.
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