Episode 52

The Mu in Muichiro (無一郎の無) is the 52nd episode of the Kimetsu no Yaiba TV anime series, and the 8th episode of its third season.

Summary
After breaking free from Gyokko's Water Prison Pot, Muichiro emerges weak, numb, and exhausted, only to watch demons about to kill Kotetsu. Seemingly unable to move and save him, his life flashes before him and he recalls everything that has led to where he is now. The memories and trauma change something in him, giving a new strength that he had never felt before and a new way to battle Upper Five.

Synopsis
After falling out of the water pot, Muichiro begins the task of removing the needles stuck into him, but he quickly feels the severe numbness in his body caused by the needles’ poison. After removing them all, he notices the unconscious Kotetsu and the bladed fish demon about to attack him, seeing more demons join the fight. Without any strength and unable to stand, he sees the demonic spawn pounce on the young smith and his life flashes before his eyes; he sees his father encouraging him to get up.

A young Muichiro struggles to stand with his load of lumber but finds the strength to rise up and run to his father. Owing to his work as a woodcutter, he would help his father cut down trees and enjoyed doing it, seeing the smile on his face as he worked. One night, as a storm raged, his sick mother’s condition begins to worsen. Muichiro tries to tell her that their father had gone out to pick medicinal herbs; feeling her high fever, he changes her wet rag and puts on another futon as comfort. She only mutters, “I'm cold”, leading Muichiro to hug her and state that his father will come soon. Outside in the severe weather, Muichiro’s father reaches a cliff face and sees the herbs.

He struggles to reach for them, stretching his arm to take a bundle for his wife. As he inches ever closer, the rock he is standing on suddenly breaks and he falls to his death, clutching the herbs in his hand. His mother would succumb that same night. Without both parents at the age of ten, Muichiro believed he was alone, only to recall that it was when he was eleven that he was alone; he in fact had a twin brother named Yuichiro at that time. As the two walked back home from their parents’ graves, Yuichiro began to speak of his disdain towards compassion, believing that helping others is meaningless. Muichiro, hurt by his twin’s hostile remarks, speaks up and says that helping others will help themselves, as their father had said.

Hearing this, Yuichiro tells him not to believe the words of a dead man who failed to save someone. Muichiro chides him for speaking ill about their father trying to help their mother but Yuichiro states that the herbs could have never heal their condition, remarking that if he had not gone out, they would have only one dead parent. Muichiro is shocked by Yuichiro’s harsh statement but his twin bitterly spits back that he is telling the truth, ordering him to be quiet. Yuichiro tells him the Mu in Muichiro is taken from the word for incompetence, muttering that their conversation is pointless since the past cannot change. He adds that the Mu in his name also comes from meaningless, causing his twin to cry.

Muichiro recalls that he would act like his twin whenever he lost his memories, speaking in a blunt and harsh manner. He remembers that living with Yuichiro was stifling and he believed that his twin was a cold individual who hated him. Two seasons later, during spring, Muichiro went to fetch water by the river. Upon telling Yuichiro, he only expressed annoyance in him not doing so already. At the river, as he filled his buckets, he was happened upon by a white-hair woman, Amane Ubuyashiki, becoming stunned by her beauty and initially believing she was a forest spirit.

After she introduced herself as the wife of the Demon Slayer Corps’ leader, Amane stated that she had come to the mountains to give an offer. However, a hostile Yuichiro turns her away and forces her to leave. That night, Muichiro expressed to his twin his excitement when Amane had told them they were descendants of the swordsmen who used the first Breathing Style. Yuichiro ignores his glee and orders him to wash some rice. Muichiro tries to tell him that they should become swordsmen after learning about demons, believing they could help people who suffer because of them.

Listening to his twin’s optimism and belief that they can help others, Yuichiro slams his knife down onto his cutting board, silencing Muichiro. Seething with anger, he furiously asks how Muichiro could even believe he can be a swordsman when he cannot even cook rice. Stating he is exactly like their father and mother, he insults Muichiro’s continual optimism, remarking how their mother had continued working and kept her condition hidden from them and how their father had went out to get herbs in the middle of a storm.

Angrily recalling how he had told their mother to rest and how he tried to get their father to stay home, he bitterly declares that helping others is reserved for the chosen ones. Questioning what could they possibly do despite being the descendants of swordsmen, Yuichiro asks Muichiro if he truly believes they can become swordsmen, answering himself by stating that all they can and will do is die a pointless death because they have no value, just like their parents.

He claims that Amane will use them for nefarious reasons and flatly declares the conversation finished, before ordering him to help make dinner. As Muichiro tears up from his twin’s verbal lashing, he recalls that they have never spoken to each other since that day, with the exception of the day they had fought when Yuichiro had splashed Amane when she visited them again.

Since his outburst, Yuichiro had continually ignored Muichiro even when he needed help, always having a scowl painted on his face. When a particularly hot summer came, both twins found themselves always irritable; even the nights became hot and attempting to sleep became difficult with the heat and buzzing cicadas. One night, Muichiro moved about on his bed unable to sleep, sweat covering his body. He got up to take a drink and saw that Yuichiro too was awake, bothered and sweaty as well. Without warning, a demon appeared in their home, who expressed surprise that only children was at home, before turning to kill Muichiro.

Yuichiro leapt out of bed to stand in front of him, only for the demon to slash at him and sever his left arm, spraying the twins in blood. Muichiro quickly grabbed his agonized twin and moved him to the corner of the house as the demon became annoyed at Yuichiro’s screaming. The demon tells them that poor woodcutters are useless anyway and said that them being alive or dead didn’t matter, stating that their lives were worthless.

Muichiro, upon hearing the demon’s insults, suddenly lost himself in an incredibly violent rage that he had never experienced before, remarking how even recalling it now, he could not believe it happened and stating that he could not remember anything when it happened. One moment, Muichiro saw himself screaming a vicious roar from his throat and in the next, he saw the demon brutally butchered with several gardening tools and pinned with wooden stakes and stones. The demon, despite his wounds, continued to twitch in agony as he could not die. Shortly after this, sunlight shone on his body, causing him to finally burn into ash and perish. After watching it die, Muichiro dropped his weapons and walked back home, only to collapse just a short walk away from the front door. Desperately wanting to reach Yuichiro, Muichiro struggled to crawl the remaining distance. After finally making it home, he saw his twin was barely clinging to life and made his way to him. He saw that Yuichiro was praying to the gods to save his brother because, “''He’s not like me. He’s a kindhearted kid. He says he wants to help others… but I got in his way”''. Denouncing himself as the only one to blame, he prays for only himself to be punished instead and he finally recalls where the Mu in Muichiro’s name came from, as his twin began to cry and hold his bloodied hand.

Recalling Yuichiro’s statement that the Mu in Muichiro comes from “infinity”, Muichiro rises up; his faces become marked with two red cloud-like patterns as he grabs his blade and uses Mist Breathing, Fourth Form: Shifting Flow Slash, grabbing Kotetsu and eviscerating the fish demons instantly. Checking on Kotetsu, the young swordsmith tells him to not pay him heed and instead move to help Hotaru and protect the swords, to which the Hashira obliges. Gyokko, now entirely livid, watches as Hotaru continues to polish his blade and ignore him, despite now sustaining numerous slashes throughout his body and a lost eye. Notices the heavily injured Kozo nearby, he decides that killing him should finally get a reaction out of Hotaru.

Suddenly, he senses a blade approaching him and ducks down in the nick of time to avoid Muichiro’s slash. Seeing the Hashira, he becomes confused at how he managed to escape his Water Prison Pot, thinking that since he believed he would die, he did not focus on him, though the demon instead interprets it as credence to his deep concentration. He looks closely and sees the marks on his face, realizing from information given by Muzan that they are the same as on "that child with the earrings". Most confusingly for Gyokko is how Muichiro appears so nonchalantly when he is supposed to be paralyzed and how he has managed to land a slash on his shoulder.

As the Mist Hashira attacks, Gyokko points a pot at him and unleashes his Blood Demon Art, Octopus Vase Hell; enormous tentacles emerge from his pot to grab him and Kozo, snapping his blade and destroying the work shed. Gyokko wonders what Muichiro now thinks of his new elastic tentacles since they cannot be slashed. Having been knocked outside, Hotaru grabs his polishing stone, kneels down and continues his work, which is noticed by the annoyed Upper Rank. Deciding he will kill and absorb the Hashira first, he is shocked to watch the tentacles grabbing Muichiro and Kozo suddenly fall apart.

Now with his own completed blade, Muichiro thanks the swordsmith, though Kozo mentions he had only made it based on the instructions of his first smith, Tetsuido. As he wields his new blade, he is pleased to feel its balance suit him perfectly. He recalls a time when he had spoken to Tetsuido, who expressed concern that nobody could understand him, whether it is the pressures he faces, his inability to remember things, or his strive to push himself, before mentioning that he tears up when he uses the blade made for him. Stating that he is old enough to not worry about death, he instead cannot seem to stop worrying about him. As Gyokko prepares his Octopus Vase Hell and Muichiro takes a stance, he apologizes to Tetsuido for causing him to worry, but as of now, he is alright.

Watching the tentacles approaching him and empowered by his marks, the Hashira blitzes forward and uses Mist Breathing, Fifth Form: Sea of Clouds and Haze, slicing through them all with incredible speed and aiming a slash at Gyokko’s neck. The demon quickly ducks down and appears out of a new pot on top of a tree, complimenting his new speed but mentioning that he is still too slow to match how quickly he can move between pots. Unexpectedly, Muichiro asks if he believes it to be so and wonders if his senses have dulled from his age; initially confused, Upper Five becomes stunned to feel a slash on his neck.

The Mist Hashira promises to slash him properly the next time but Gyokko claims the boy shouldn’t underestimate him. He vanishes from view and appears behind Muichiro, pointing his vases to launch a volley of high-speed water jets. Muichiro expertly weaves his way through the forest to avoid them and watches as more of Gyokko's goldfish demons appear and spray hundreds of poisonous needles at him. As he evades Upper Five's incessant attacks, Muichiro recalls Yuichiro's final apology just before his death. "Muichiro. Sorry I couldn't be more gentle with you. I could just never afford to be that way. Being kind to others is one more thing that only the chosen ones can do. But Muichiro, no matter how virtuous a life you may lead, neither the gods nor Buddha will protect you in the end. That's why I thought I had to protect you. Muichiro. You're not like me. For the sake of someone other than yourself, you can exert infinite strength. You're one of the chosen ones!"

As the demon unleashes his octopus tentacles to grab Muichiro, the Mist Hashira leaps up and evades them all with ease, before he slashes the vases right out of Gyokko's hands and stares at his opponent's next move, enraging the Upper Rank greatly.

Characters in Order of Appearance

 * Muichiro Tokito
 * Kotetsu
 * Muichiro's father
 * Muichiro's mother
 * Yuichiro Tokito
 * Amane Ubuyashiki
 * Gyokko
 * Hotaru Haganezuka
 * Kozo Kanamori
 * Tetsuido