Is Upper Rank 1 Related to Tanjiro? The Truth Behind the Demon Slayer’s Ancestry


Tanjiro Kamado is the main protagonist of the popular manga and anime series “Demon Slayer: Kimetsu no Yaiba”. He is a kind-hearted and courageous young man who becomes a demon slayer after his family is slaughtered by the demon king Muzan Kibutsuji. Along his journey, he encounters many powerful foes, including the Twelve Kizuki, the elite group of demons who serve Muzan. One of them is Upper Rank 1, also known as Kokushibo, the strongest of the Twelve Kizuki and a formidable swordsman. But is Upper Rank 1 related to Tanjiro? This is a question that many fans have wondered about, especially after the reveal of Kokushibo’s true identity and past. In this article, we will explore the possible connection between Upper Rank 1 and Tanjiro, and the implications it has for the story and the characters.

Who is Upper Rank 1?

Upper Rank 1, or Kokushibo, is a demon affiliated with the Twelve Kizuki, holding the highest position among them. He is a tall and muscular man with pale skin, long black hair with red tips, and three sets of eyes on his face. He wears a purple-and-black hexagonal patterned kimono and black hakama pants. He wields a katana that can change shape and size according to his will, and he is proficient in the Moon Breathing, a sword technique that allows him to create crescent-shaped slashes of energy. He is also extremely durable, fast, and strong, being able to withstand and counter the attacks of several Hashira, the elite demon slayers, at once.

Kokushibo is a ruthless and arrogant demon who looks down on humans and weak demons alike. He is obsessed with strength and perfection, and he seeks to surpass his twin brother, Yoriichi Tsugikuni, the strongest demon slayer in history and the creator of the Breath of the Sun, the original sword technique that all other breaths are derived from. He is also loyal to Muzan, whom he considers his savior and master, and he is willing to do anything to fulfill his orders and goals.

Kokushibo’s Human Past

However, Kokushibo was not always a demon. In fact, he was once a human named Michikatsu Tsugikuni, a former demon slayer and the older twin brother of Yoriichi Tsugikuni. He lived during the Sengoku Era, nearly five centuries ago, in a time of war and chaos. He was born into a noble family, and he was expected to inherit his father’s position and wealth. He was also a talented swordsman, and he trained diligently to become stronger. He had a close relationship with his brother, who was born with a frail body and a weak constitution. He often protected him from bullies and taught him how to use a sword.

However, everything changed when Yoriichi awakened his Demon Slayer Mark, a rare phenomenon that grants a demon slayer enhanced physical abilities and a shortened lifespan. Yoriichi’s mark took the form of a sun on his forehead, and it also gave him access to the Breath of the Sun, the ultimate sword technique that can harm Muzan and his cells. With his newfound power, Yoriichi became a legend among the demon slayers, and he single-handedly killed many demons, including Upper Rank 6, Doma, and Upper Rank 4, Hantengu. He also confronted Muzan himself, and he almost killed him, but he spared his life out of pity and compassion.

Michikatsu, on the other hand, became jealous and resentful of his brother’s achievements and popularity. He felt inferior and overshadowed by him, and he developed a bitter rivalry with him. He also became obsessed with obtaining the Demon Slayer Mark and the Breath of the Sun, but he failed to do so, despite his efforts and sacrifices. He even married a woman he did not love, and he had two children with her, hoping to pass on his bloodline and create a successor who could surpass Yoriichi. However, his wife and children died of illness, and he was left alone and miserable.

One day, he encountered Muzan, who offered him a chance to become a demon and gain eternal life and power. Michikatsu accepted his offer, and he became Kokushibo, the Upper Rank 1. He also abandoned his human name and identity, and he devoted himself to Muzan and his cause. He also severed his ties with his brother, and he vowed to kill him and take his place as the strongest swordsman. However, he never got the chance to do so, as Yoriichi died of old age before they could meet again.

Is Upper Rank 1 Related to Tanjiro?

So, is Upper Rank 1 related to Tanjiro? The answer is no, they are not related by blood. Tanjiro is not a descendant of Michikatsu, nor does he have any connection to his family. Tanjiro’s family was a simple and humble one, living in the mountains and making a living by selling charcoal. They had no ties to the noble Tsugikuni clan, nor did they have any involvement with the demon slayers or the demons.

However, Tanjiro does have a connection to Yoriichi, Michikatsu’s twin brother. Tanjiro is a distant relative of Sumiyoshi, a friend of Yoriichi who inherited his earrings and his journal. Sumiyoshi passed on these items to his descendants, and they eventually reached Tanjiro’s father, who taught Tanjiro the Dance of the Fire God, a ritual that is actually a variation of the Breath of the Sun. Tanjiro also inherited his father’s earrings, which bear the same design as Yoriichi’s mark. These earrings are what drew the attention of Muzan and Kokushibo, who recognized them as Yoriichi’s symbols.

Tanjiro also resembles Yoriichi in appearance and personality. They both have dark hair, red eyes, and a kind and compassionate nature. They also share a strong sense of justice and a determination to protect their loved ones and defeat Muzan. However, they also have some differences, such as their fighting styles and their views on demons. Tanjiro uses the Water Breathing and the Dance of the Fire God, while Yoriichi used the Breath of the Sun. Tanjiro also sympathizes with some demons and tries to give them a peaceful death, while Yoriichi was more ruthless and merciless towards them.


In conclusion, Upper Rank 1 is not related to Tanjiro, but he is related to Yoriichi, the legendary demon slayer who is Tanjiro’s distant ancestor and look-alike. This connection creates a complex and tragic relationship between the two characters, as they are both bound by fate and history, but they are also enemies and opposites. Tanjiro represents the human side of Yoriichi, while Kokushibo represents the demon side of Michikatsu. Tanjiro also carries on Yoriichi’s legacy and mission, while Kokushibo tries to destroy it and surpass it. Their final confrontation is a clash of ideals and wills, as well as a culmination of their personal and family drama.