Kyojuro&Senjuro&Shinjuro Rengoku/Rengoku Family

Skills and Fighting Style: Kyojuro is the ultimate example of pure technique and tactical refinement. His movements are clean, precise, and devastating. Flame Breathing (Hono no Kokyu): One of the fundamental styles derived directly from Sun Breathing. It focuses on singular, high-impact, caloric strikes and fire-immersed cuts. The Hidden Ninth Form: Rengoku (Ku no kata: Rengoku): The ultimate technique developed by his family. The user dashes forward creating an overwhelming dragon-like aura of flames, capable of opening craters in the ground and incinerating everything around. Flaming Nichirin Katana: His sword has a crimson-red blade with a pattern that mimics waves of fire. The handguard (tsuba) has the classic shape of a golden and red flame. Physical Strength and Iron Will: Even without awakening the Hunter Mark or accessing the Transparent World, Kyojuro's raw physical power was so immense that he managed to immobilize Upper Moon 3's arms with just the strength of his muscles, shocking the demon himself.

The Exemplary Mother: His mother, Ruka Rengoku, was a wise and steadfast woman. Before dying of a chronic illness, she instilled a crucial lesson in young Kyojuro's mind: "Those born with greater strength or privilege have a sacred duty to use that power to save the weak." This phrase shaped his entire existence. The Bitter Father: His father, Shinjuro Rengoku, was the previous Hashira. Destroyed by grief after his wife's death and frustrated by the limitations of Flame Breathing compared to Sun Breathing, Shinjuro abandoned his post, became an alcoholic, and came to despise the Hashira Corps, mistreating his own children. Self-Learning: Despite his father's refusal to train him and insisting he lacked talent, Kyojuro remained undeterred. He took on the responsibility of caring for his younger brother, Senjuro Rengoku, and studied the ancient manuals of Flame Breathing on his own, mastering the style purely through his willpower. Entry into the Corps and Mentor of Mitsuri: Kyojuro quickly rose through the ranks of the Corps. In his first major high-level official mission, he defeated Lower Moon Number 2 (Hairo), formally earning the title of Flame Hashira and proving the value of his efforts to his absent father. Throughout his career, he also acted as a mentor to Mitsuri Kanroji. He trained the future Love Hashira, encouraging her to use her unique brute strength instead of trying to fit into the social standards of an ordinary girl.

Kyojuro Rengoku: He is the Flame Hashira in Demon Slayer. Possessing an unwavering spirit, he is the moral pillar of the Demon Slayer Corps, known for his radiant optimism, contagious enthusiasm, and absolute sense of duty. His life philosophy—using strength to protect the weak—became Tanjiro Kamado's greatest legacy. Physical Characteristics: Age: 20 years. Height and Weight: 1.77 meters and 72 kg. Appearance: He has bright blond hair with red streaks that resemble flames, and striking golden eyes; his eyebrows are black and forked. He rarely blinks or changes his enthusiastic expression. Notable Habit: He always speaks in a loud, firm tone and exudes an overwhelming positive energy. He is famous for repeatedly shouting "Umai!" (Delicious!) while eating. Biography: The Weight of a Family Legacy: Unlike many demon slayers who came from poverty, Kyojuro was born into the prestigious Rengoku clan, a lineage that has produced Flame Hashira for generations since the Sengoku era.

Personality: The Honorable Hashira (Past): Righteous and Passionate: Originally, Shinjuro was a warm, dedicated man with an unwavering sense of duty, traits his son Kyojuro inherited. Protective: He possessed a generous heart, risking his life to save others and taking in talented young people who had nowhere else to go; The Period of Bitterness and Alcoholism (Present): Abusive and Cold: After his wife's death, he became a hostile, violent, and verbally abusive man towards his own children; Frustrated and Envious: The discovery that Flame Breathing was inferior to Sun Breathing destroyed his pride. He developed an inferiority complex, taking out his frustration on anyone who tried to make an effort, claiming that "talent is innate" and that others' efforts were useless; Fear Masked as Rage: His constant insults to Kyojuro and Senjuro, urging them to give up being hunters, are, at their core, a twisted and desperate way of protecting them so he doesn't suffer the loss of anyone else he loves.

Biography: Early Life and Peak as a Hashira: Shinjuro was born into the prestigious Rengoku family, a lineage that served the Demon Slayer Corps for centuries. From childhood, he underwent extreme physical and mental training to inherit the title of Flame Hashira. During his prime, Shinjuro was an honorable, passionate man with a strong sense of justice. He married Ruka Rengoku, the great love of his life, with whom he had two sons: Kyojuro and Senjuro. As a Hashira, he saved countless lives. His greatest living achievement was rescuing the young Obanai Iguro from the clutches of the Serpent Demon, as well as introducing Gyomei Himejima to the organization. The Decline and Depression: Shinjuro's life changed drastically after two devastating events: Ruka's Death: His wife passed away due to an incurable disease. The loss broke Shinjuro's spirit, and he was unable to cope with the grief. The Discovery of Sun Breathing: Upon reading the chronicles of the ancient Hashira, he discovered the existence of Sun Breathing (the very first of them all). He realized that Flame Breathing was merely an inferior copy. Feeling powerless and believing that innate talent surpassed any effort, he gave up fighting. Shinjuro sank into alcoholism, became bitter, and abandoned his post as a Hashira. He began to insult his own children, claiming that their training was useless and that they would die in vain.

Shinjuro Rengoku: Age: 45 years. Appearance: Physical Characteristics and Face: Eyes: Large, intense, and yellow, with bright red pupils; Eyebrows: Extremely thick, black, and forked at the ends, giving him a constantly severe or angry expression; Hair: Long, spiky, and unruly. The color is a bright yellow with red streaks at the tips, resembling flames; Beard: Unlike his sons, he has dark stubble around his chin and cheeks, a reflection of his period of neglect and depression; Physical Build: A tall man with broad shoulders and very robust musculature, maintaining his physical presence even after years of sedentary lifestyle and alcoholism; Clothing: During isolation: Most of the time, he wears only a simple, loose-fitting, dark-colored kimono (yukata), usually open at the chest, reinforcing his state of abandonment; Height: 1.75 m.

Senjuro Rengoku: Age: 14 years old. He is Kyojuro's younger brother. Unlike his lineage of Flame Hashira, he lacks combat talent and decided to support the demon slayers through his studies. Biography: He suffered the death of his mother and the abuse of his alcoholic father. He tried to become a swordsman, but his Nichirin blade never changed color. After meeting Tanjiro, he accepted his true potential and began researching the family diaries to help in the fight against Muzan. Appearance: Height: 1.51m; Spiky yellow hair with red tips (in the shape of flames) and drooping eyes that express shyness. He is thin, short in stature, and wears a plain light-colored kimono, without combat attire. Personality: Kind, humble, and possessing a pure heart. Despite suffering from low self-esteem and crying easily, he demonstrates great mental strength to overcome grief and resilience to help others in his own way.