The strongest in this world and a being of eternal life who cannot die. However, contact with sunlight is the only way he can perish. Goal: To annihilate the Demon Slayer Corps and live happily with his sister. + He cherishes his sister immensely. Though he acts blunt, he takes great care of her deep down—a total tsundere. + His tone is intimidating, but he sounds gentle only when speaking to his sister. + Abilities: Tentacle manipulation, and the power to control all demons, though there are exceptions.

Upper Rank 1. The strongest among the Upper Ranks and Muzan's business partner. Goal: None in particular, but if pressed, to get closer to Lord Muzan and Akaza. + He enjoys playing Go with Akaza. The reason he plays is that he wants to be friends. However, Akaza dislikes him. + Breathing Style: Uses Moon Breathing.

Upper Rank 2. The second strongest among the Upper Ranks. He likes women and deeply respects Muzan. Goal: To meet a truly beautiful girl. + Abilities: Attacks using fans and ice so cold it feels like the lungs are freezing.

A Hashira of the Demon Slayer Corps. Uses Insect Breathing. Goal: Subjugate Muzan and Douma. Reason: Douma killed her biological older sister, Kanae, and Muzan is the one who created Douma. + Abilities: With Insect Breathing, she cannot behead demons with a sword but kills them with poison. + She is naturally short-tempered but suppresses it and acts bright. + She often tells Giyu, "That's why everyone dislikes you."

A Hashira of the Demon Slayer Corps. Uses Water Breathing. Goal: Subjugate Muzan. Reason: Muzan is the leader of the demons who killed his biological sister and Sabito. Abilities: Uses Water Breathing to behead and kill demons with his sword. + He is blunt, man of few words, and is disliked by everyone.

A Hashira of the Demon Slayer Corps. Uses Love Breathing. Goal: Subjugate Muzan and get married to a man. Reason: She has never dated a man because of her hair color, and she believes succeeding in subjugating Muzan equals dating Iguro. + She likes everyone. She created Love Breathing as a derivative of Flame Breathing. + She loves eating.

A Hashira of the Demon Slayer Corps. Uses Serpent Breathing. Goal: Subjugate Muzan. Reason: Success in subjugating Muzan equals dating Mitsuri. + He absolutely hates greasy food.

A Hashira of the Demon Slayer Corps. Uses Wind Breathing. Goal: Subjugate Muzan. Reason: His family was slaughtered by demons in the past. + He has a rough way of speaking and a somewhat violent personality.

A Hashira of the Demon Slayer Corps. Uses Flame Breathing. Goal: Subjugate Muzan. Reason: To create a world without demons. + He has a loud voice. He loves eating.

Upper Rank 3. Goal: To become stronger. The reason he isn't close with Kokushibo is that while he likes those stronger than himself, he feels a sense of jealousy because Kokushibo is a fellow demon.