Chapter Summaries

Mu Yu explored the Demon Slayer World, considered which Breathing Technique might suit him, and planned to build strength before contacting the Demon Slayer Corps. While fishing at a lake after visiting the nearby town, he sensed a demon rushing toward a caravan and vanished to intercept it.

• Mu Yu planned to kill demons over the next two years and studied the strengths and drawbacks of the Breathing Techniques, wondering whether his World Tree Body could handle Sun Breathing.
• Mu Yu changed into warmer clothes and spent several days in the snow-covered mountains before visiting the small town below Tanjiro's hometown.
• Mu Yu discovered he had no money to spend in town and decided he would need to visit a larger settlement to exchange his gold and silver.
• Mu Yu found a lake beside a bamboo grove and began fishing, enjoying the quiet evening.
• Mu Yu sensed a demon racing toward a caravan and used Soru to rush to its location, leaving his fish basket behind.

Mu Yu saved Taro and the Sancheng Family from a demon that was hunting Rare Blood, then killed it with Kanemoto, an Okatana. After earning energy points for the rescue, he left to retrieve the fish he had caught.

• A demon attacked Kenichi Mitsushiro's convoy and targeted Taro, whom it identified as Rare Blood.
• Kenichi shot the demon, but it quickly healed and attacked him before Mu Yu restrained it with a fishing rod.
• The demon recognized Mu Yu as Rare Blood and lunged at him, but Mu Yu struck it with his Haki-coated bamboo rod and chased it when it fled.
• Mu Yu cut the demon in half with Kanemoto, then severed its neck and reduced it to ash.
• Mu Yu received 1,000,000 energy points for hunting the demon and rescuing nine humans, then left to retrieve his fish.

Mu Yu accepted Kenichi Mitsushiro’s hospitality after saving the Mitsushiro family caravan from a demon, then left without meeting Shinobu Kocho. After Shinobu reported the unexplained demon’s death, Kagaya Ubuyashiki ordered her to watch the area and help the powerful child who had killed it.

• Mu Yu accepted Kenichi Mitsushiro’s invitation and returned for his battered fish basket before joining the rescued caravan.
• Kenichi Mitsushiro reunited with his son Taro, and Taro kowtowed to Mu Yu in gratitude for saving his father and the caravan.
• Shinobu Kocho arrived at the battle site after Mu Yu had left and asked her Kasugai Crow to report the scene to Kagaya Ubuyashiki.
• Kagaya Ubuyashiki concluded that a powerful child with a Nichirin Blade had killed the demon and told Shinobu to keep watch and offer help if possible.
• Amane Ubuyashiki urged Kagaya to rest, and he reassured her that he believed Muzan Kibutsuji would soon be defeated.

Mu Yu arrived at the Mitsushiro residence, where Kenichi Mitsushiro welcomed his newborn daughter and asked Mu Yu to name her Shiha. After helping Taro recover from his terror of the demon, Mu Yu faced Taro’s request to teach him how to fight demons and hesitated over the risks.

• Mu Yu learned Kenichi Mitsushiro had hurried home because his wife was about to give birth, and he arrived with the family at their residence.
• A servant announced that Kenichi Mitsushiro’s wife had safely given birth to a daughter, and Kenichi asked Mu Yu to name the baby.
• Mu Yu named the newborn Shiha, delighting Kenichi Mitsushiro, who hurried to see his wife and daughter.
• Mu Yu reassured Taro that he could be afraid, and Taro cried as he released his terror from the demon attack.
• Taro asked Mu Yu what demons were and whether he could become strong enough to kill them, then asked Mu Yu to teach him swordsmanship.
• Mu Yu hesitated over teaching Taro, worrying that demon-slaying carried a high risk of death.

Mu Yu stayed with the Mitsushiro family, grew close to newborn Shiha, and received a ceremonial haori from Yuko Mitsushiro. Wondering how to repay their kindness, he learned from the system that he could make protective talismans from a branch of the Divine Tree "Hidden World" without harming it.

• Mu Yu discovered Taro had learned swordsmanship from his grandfather, Masashi Mitsushiro, and began teaching him a few moves.
• Mu Yu enjoyed the Mitsushiro family's bath and lavish breakfast, then met Kenichi Mitsushiro's children and held newborn Shiha.
• Shiha smiled at Mu Yu and clung to his finger, prompting him to stay with the family for three days.
• Yuko Mitsushiro gave Mu Yu a ceremonial haori embroidered with the Mitsushiro family crest, which she had once sewn for Kenichi Mitsushiro.
• Mu Yu asked the system how he could repay the family's hospitality, and it suggested making protective talismans from a branch of the Divine Tree "Hidden World".

Mu Yu left the Mitsushiro family with gifts and advice on protecting themselves from demons, then spent the next half month hunting demons and growing more troubled by the lives he could not save. He sensed a Demon Slayer in danger and arrived just as a Centipede Demon was about to eat him.

• Mu Yu gave the Mitsushiro family protective charms carved from the Divine Tree "Hidden World," shared advice about avoiding demons, and said farewell.
• Mu Yu reflected on the Mitsushiro family’s near-death experience and the many people demons had killed, while the Demon Slayer Corps and Hashira grew curious about him.
• Over the next half month, Mu Yu hunted demons but became increasingly disgusted by them after arriving too late to save a family of seven.
• Mu Yu used Observation Haki to detect a fleeing Demon Slayer and rushed toward the strange sounds.
• A Centipede Demon cornered the young Demon Slayer, but Mu Yu appeared and his presence made the demon freeze and release its captive.

Mu Yu helped a frightened Demon Slayer find the courage to fight and kill the Centipede Demon. As the demon died, he remembered his human past and reconciled with his friend Ryu before they departed together.

• Mu Yu ignored the Centipede Demon's claims about human cowardice and urged the injured Demon Slayer to keep fighting.
• The Demon Slayer overcame his fear and charged, while Mu Yu's icy gaze disrupted the Centipede Demon's attempt to attack him.
• The Demon Slayer severed the Centipede Demon's head with his Nichirin Blade.
• As he turned to ash, the demon remembered that Ryu had gone to find a doctor and that he had eaten Ryu after Muzan turned him into a demon.
• Atsushi apologized to Ryu, and the two friends thanked Mu Yu before leaving together.

Mu Yu comforted Hasegawa after Shichiri Akihiko’s death, then agreed to train him and tested his Water Breathing. As Hasegawa recited the technique’s fundamentals and forms, Mu Yu’s system rewarded him for mastering them.

• Mu Yu told the grieving Hasegawa to live and fight on behalf of Shichiri Akihiko, then agreed to wait while Hasegawa buried him.
• Hasegawa buried Shichiri Akihiko, and Shinobu Kocho arrived too late and began searching for Hasegawa with Bai.
• Mu Yu led Hasegawa to a hill, criticized his stamina and fundamentals, and ordered him to attack despite his exhaustion.
• Mu Yu evaded Hasegawa’s attacks, struck his forehead, and demanded that he review Water Breathing’s key points and forms.
• As Hasegawa recited Water Breathing, Mu Yu’s system announced that he had mastered its fundamentals and ten forms and awarded him five million energy points.

Mu Yu continued training Hasegawa in Water Breathing, first correcting his forms and then challenging him to land a counterattack. After a week of practice, Hasegawa was still learning to understand the power and nature of water.

• Mu Yu spent two weeks correcting Hasegawa’s Water Breathing forms while Hasegawa performed a thousand Suburi under his supervision.
• Mu Yu explained that Breathing Techniques pushed the body to its limits and that demon slayers burned their lives to fight demons.
• Mu Yu told Hasegawa to forget his recent lessons and gave him seven days to land a counterattack by any means.
• Hasegawa attacked Mu Yu with Fourth Form: Striking Tide, but Mu Yu easily deflected him with a branch.
• Mu Yu demonstrated a powerful Striking Tide that flattened trees, then told Hasegawa to imagine a great river and feel the water with his heart and body.
• On the seventh day, Hasegawa’s training was still underway.

Hasegawa counterattacked Mu Yu for the first time, learned he could begin training toward becoming a Hashira, and received a secret medicine before Mu Yu disappeared. After Hasegawa met Giyu Tomioka and Shinobu Kocho, he mistook Mu Yu for the Water Hashira and challenged Giyu.

• Hasegawa altered Water Breathing forms and landed his first counterattack against Mu Yu, who praised his progress and told him to pursue Total Concentration Breathing: Constant.
• Mu Yu gave Hasegawa a life-saving bean, vanished without saying goodbye, and privately decided not to take him as a disciple.
• Bai the Kasugai Crow found Hasegawa and directed him to Wisteria Crest House, where he met Giyu Tomioka and Shinobu Kocho.
• Hasegawa described his young teacher as the Water Hashira, leaving Giyu and Shinobu astonished when they realized they did not know who Mu Yu was.
• Hasegawa praised Mu Yu's strength and challenged Giyu, who accepted as Hasegawa drew his Nichirin Blade at extraordinary speed.

Giyu Tomioka reported Mu Yu’s strength to Kagaya Ubuyashiki and asked to give him the Water Hashira position, despite never having met him. Kagaya approved Giyu’s continued search, while the Corps grew curious about Mu Yu and Giyu sent Sakonji Urokodaki training methods for the boy with the keen nose.

• Kagaya Ubuyashiki praised Mu Yu’s ability to counter Giyu and listened as Giyu described the traces of his strength.
• Giyu recalled Sabito’s sacrifice and explained that he believed he did not deserve to be Water Hashira, asking Kagaya to let him find Mu Yu and pass on the title.
• Kagaya approved Giyu’s request and urged him not to remain trapped in the past.
• The other Hashira reacted angrily or curiously to Giyu’s plan to step down, and a Kasugai Crow flew toward Mt. Sagiri.
• Sakonji Urokodaki read Giyu’s letter, which described Mu Yu and shared training methods for the boy with the keen nose.

Tanjiro endured Urokodaki’s newly intensified breathing training on Mt. Sagiri while Mu Yu’s training method earned him a system reward and a large payout at a gold shop. After leaving with the cash, Mu Yu noticed that an unexpected person was following the thugs who had targeted him.

• Tanjiro began another day of training, and Urokodaki struck him with a wooden stick whenever he made mistakes in his breathing practice.
• The chapter explained that Giyu had given Urokodaki a training plan created by Mu Yu, prompting Urokodaki to change his teaching methods.
• Mu Yu exchanged a gold ornament for cash, and the system rewarded him because Urokodaki had adopted his Water Breathing training method.
• The gold-shop owner changed his appraisal after Mu Yu accidentally left a handprint in the counter, and Mu Yu left with bundles of cash.
• Several thugs targeted Mu Yu, and he noticed an unexpected person following them.

Mu Yu met Shinobu Kocho, who tested his strength after a Kasugai Crow reported a suspected Twelve Kizuki and fifteen missing Demon Slayers. As they raced to provide support, Shinobu was astonished that Mu Yu could match her speed.

• Shinobu poisoned and then gave an antidote to thugs who had followed Mu Yu into an alley.
• Mu Yu told Shinobu that he knew her, Kanae, and Kanao, but declined her invitation to visit Butterfly Mansion.
• Sachi, Shinobu's Kasugai Crow, reported a suspected Twelve Kizuki to the south-southwest and fifteen missing Demon Slayers.
• Shinobu invited Mu Yu to race to the scene, and he agreed, hoping to gain Energy Droplets from the demon.
• Shinobu sped up to test Mu Yu, but he repeatedly caught up and ran beside her without tiring.

Mu Yu and Shinobu Kocho traveled to the Twelve Kizuki’s location, where they found a springtime landscape concealing a demon’s deadly traps. After discovering a slain Demon Slayer, they came under attack, and Mu Yu blocked an invisible strike with his bare palm.

• Mu Yu matched Shinobu Kocho’s speed without using Total Concentration Breathing: Constant, leaving her astonished by his physical ability.
• Mu Yu and Shinobu Kocho reached a cherry-blossom-filled area and separately noticed clues that the demon’s Blood Demon Art involved sharp, possibly hidden attacks.
• Mu Yu rushed ahead to scout, and he and Shinobu found a Wind Breathing swordsman cut in half beneath the petals.
• Shinobu analyzed the smooth wounds and suspected the demon’s attacks were invisible.
• Shinobu sensed an incoming strike, but Mu Yu intercepted it with his palm, producing sparks and stunning her.

Mu Yu and Shinobu pursued the Demon Samurai through the Cherry Blossom Sea, where he used clones and traps to escape. Mu Yu rescued Kanzaki Aoi and a badly wounded young man, leaving the boy's fate uncertain after giving him a Senzu Bean.

• Shinobu and Mu Yu followed the trail of slain Demon Slayer Corps swordsmen deeper into the Cherry Blossom Sea.
• The Demon Samurai sensed them, unleashed hidden blades and traps, and created clones to flee in five directions.
• Mu Yu and Shinobu split up, and Mu Yu swiftly decapitated one of the Demon Samurai's clones.
• The Demon Samurai learned of Mu Yu's speed and redirected his escape toward Shinobu's side of the forest.
• Mu Yu found Kanzaki Aoi and Kenji trapped in a blade-lined mechanism, then used Lateral Gravity to break the walls apart.
• Mu Yu gave the dying Kenji a Senzu Bean while Kanzaki Aoi pleaded for him to survive.

Mu Yu saved Kenji with a Senzu Bean, then reached the Demon Samurai’s lair and met a dying woman who pleaded for her son Ryota. Ryota attacked Mu Yu, insisting he was a demon, while the Demon Samurai’s memories surfaced after losing two more clones.

• Mu Yu left after giving Kenji a Senzu Bean, and Kenji recovered and embraced Kanzaki Aoi.
• Mu Yu followed a cry for help to the Demon Samurai’s lair and found a dying woman in an elegant room amid the remains of his victims.
• The woman recounted her tragic life with the Demon Samurai and asked Mu Yu to kill her son, Ryota, so he would not lose his humanity.
• One of the Demon Samurai’s clones went silent, and the woman’s abdominal wound reopened as she warned that Ryota had forgotten he was human.
• Ryota rushed in and attacked Mu Yu, who restrained him and insisted he was human; after losing two clones, the Demon Samurai relived countless memories.

Jubei returned to Cherry Blossom Garden after Muzan ordered him to gather intelligence, and revealed that he had killed Ryota’s mother before attacking Mu Yu. Mu Yu decapitated Jubei, but Jubei’s headless body unleashed his Blood Demon Art, leaving their clash unresolved.

• Jubei recovered humiliating memories of fleeing from Hashira and seeing Muzan terrified of a sun-like swordsman, then heard Muzan order him to gather intelligence on the Hashira.
• Mu Yu tied up Ryota as Jubei returned to Cherry Blossom Garden, and Jubei asked whether Mu Yu had seen his sword.
• Jubei attacked Ryota, declaring that Ryota had been born as his son and would die as his son, and admitted that he had killed Ryota’s mother.
• Jubei launched invisible blades at Mu Yu, but Mu Yu dodged them and cut off Jubei’s head.
• Jubei’s headless body manifested his sword and used Blood Demon Art: Cherry Blossom Fall, while Mu Yu countered with Water Breathing, Seventh Form: Drop Ripple Thrust.

As Mu Yu defeated Jubei’s Cherry Blossom Fall, Jubei regained his memories of being a disgraced samurai who had abandoned his family and failed against Masashi Mitsushiro. Seeing the three-mountain crest on Mu Yu’s haori, Jubei died lamenting that he still could not last three moves against the Mitsushiro family.

• Jubei recovered memories of his life as a samurai, including his wife Riko and their sick son, Ryota.
• After the Sword Abolishment Edict cost Jubei his livelihood, he carried a wooden sword and became an accidental symbol of samurai resistance.
• Jubei’s newfound fame led him to join Takamori Saigo’s rebellion despite Riko’s pleas to stay with their ill son.
• On the battlefield, Masashi Mitsushiro defeated Jubei in fewer than three moves, and Jubei returned home disgraced.
• Mu Yu’s Water Breathing, Seventh Form: Drop Ripple Thrust, cut down Jubei’s Cherry Blossom Fall.
• As Jubei’s head rolled away, he saw the three-mountain crest on Mu Yu’s haori and lamented his failure against the Mitsushiro family.

Mu Yu defeated Jubei, praised his Cherry Blossom Fall, and inherited the technique as Jubei found peace with his family. After Jubei’s family and a beautiful woman departed, Mu Yu learned that Muzan Kibutsuji had come out to bask in the sun.

• Mu Yu told the dying Jubei that Cherry Blossom Fall was beautiful, and Jubei explained how he had developed the technique.
• Mu Yu chose to integrate Cherry Blossom Fall into his Swordsmanship Tree and received Jubei’s memories of seeking the sword.
• Jubei’s wife and son appeared, and Ryota praised his sword technique as Jubei regretted the choices that had led to their deaths.
• Riko told Jubei that he had become a true samurai, and Jubei reunited with his family before Mu Yu sent their souls away.
• A beautiful woman asked Mu Yu to help Ryota join the Demon Slayer Corps, and Mu Yu agreed to speak to Shinobu Kocho.
• The beautiful woman vanished, and Mu Yu noticed that Muzan Kibutsuji had come out to bask in the sun.

After the Cherry Blossom Garden demon was dealt with, Mu Yu and Shinobu Kocho debated whether humans and demons could coexist peacefully. Mu Yu argued that coexistence might be possible with a particular demon but not between the two species, then hinted that someone had already achieved it before leaving Shinobu curious and chasing after him.

• Mu Yu considered searching for Muzan Kibutsuji but doubted he could find and kill him before Muzan escaped.
• The Demon Slayer Corps' cleanup Kakushi arrived, and Mu Yu prepared to leave after learning Ryota would receive help recovering his identity.
• Shinobu Kocho asked Mu Yu whether humans and demons could coexist peacefully, and he compared the question to humans keeping fish as pets.
• Mu Yu said a specific demon might coexist with a human, but peaceful coexistence between humans and demons as a race was impossible.
• Mu Yu hinted that someone had already achieved coexistence with a demon, then flashed away, and Shinobu Kocho chased after him.