Mirza Aaqib Beg
In ‘Demon Slayer: Kimetsu no Yaiba’ season 3 or ‘Demon Slayer: Kimetsu no Yaiba Swordsmith Village Arc’ episode 8 titled ‘The Mu in Muichiro,’ Muichirou finally recalls his childhood. It turns out that he lost his parents tragically on the same night, while his brother became cold and distant following the incident. Before the brothers could reconcile, Yuichirou also died after a demon attacked their house.
Muichirou’s Tragic Childhood
After Muichirou manages to free himself from the pot, he painfully takes out all the poisoned needles from his body. He sees Kotetsu lying unconscious right in front of him and realizes that he is in danger of being attacked by the demons close to him. The Mist Hashira tries to move but because of the effect of the poison, he feels heavy and weak. That’s when he finally remembers his childhood memories.
Many years ago, Muichirou used to live with his parents. His father was a kind-hearted man who used to work hard. Unfortunately, his mother was quite sick and during one stormy night, her condition deteriorated. His father went to get some herbs to help her but unfortunately died after falling. As if this was not bad enough, Muichirou’s mother passed away on the same night. Luckily, he was not alone as he had a twin brother named Yuichirou.
But the death of their parents made Yuichirou really bitter. Mr. Ubayashiki’s wife Miss. Amane visited their home a few days later to inform them that they were descendants of elite swordsmen. She wanted them to join the Demon Slayer Corps but Yuichirou’s bitterness overpowered everything else and he even attacked her once. Meanwhile, the brother slowly grew apart and stopped talking altogether. One ordinary night, they were attacked by a demon.
When Yuichirou got severely injured, Muichirou lost control of his emotions and the next thing he could remember was seeing the body of the demon on the ground wreathing in pain. When he returned to his brother, he saw him at death’s door pleading to god that he lets Muichirou survive the ordeal. Yuichirou truly believed that the “mu” in Muichirou meant infinity and he wanted his brother to achieve great things in life.
What is the Demon Slayer Mark?
As memories of his brother’s death finally return, Muichirou manifests a distinct marking on his face. Although he has been struggling moments earlier, he feels a renewed energy and easily saves Kotetsu from the demons that are approaching him. Kotetsu is selfless even in his terrible condition and asks Muichirou to save the sword instead. Meanwhile, Gyokko is still absorbed by Haganezuka’s craftsmanship and is completely overcome by his seething rage.
Therefore, he notices Muichirou at the very last moment and barely saves himself from getting decapitated using his blood demon art. Gyokko realizes that the Mist Hashira appears different, so he unleashes an attack called Octopus Vase Hell that destroys the entire shed. Muichirou is caught in large octopus-like arms but manages to free himself by cutting them off. Contrary to Gyokko’s belief, the Mist Hashira is incredibly fluent and flawless with his attacks and almost manages to decapitate him one more time.
Muichirou’s incredible powers and recovery are hard to explain considering he was struggling for his life just a few minutes earlier but something changed after he unknowingly manifested the marks on his face. It turns out that the marks on his face are actually known as the Demon Slayer Mark and they were first manifested by Yoriichi during the Sengoku Era. Yoriichi was the one who realized that they can be inherited by the mere presence of a marked demon slayer, so he spread the marks to as many swordsmen of his time as possible.
The manifestation of the Demon Slayer mark comes with much physical and combat skillset improvement some of which includes an increase in physical strength and reflex. The demon slayer also gains access to the transparent world, which allows one to see through the enemies’ skin and decipher the weakness that could be used in combat. For the reasons mentioned above, Muchirou suddenly seems invincible as though he was never hurt or poisoned. His heightened state of awareness and his powers can directly be attributed to the Demon Slayer mark.
Read More: Demon Slayer: Kimetsu no Yaiba Season 3 Episode 7 Recap and Ending, Explained
