WARNING: The following contains spoilers for Demon Slayer: Kimetsu no Yaiba Vol. 18, by Koyoharu Gotouge, John Werry and John Hurt, available in English from Viz Media now.
The latest translated manga volume of Demon Slayer: Kimetsu no Yaiba, Volume 18, which collects Chapters #152-160, features Tanjiro's rematch against Akaza and Kanao's vengeful clash with Doma. As the Demon Slayers face Muzan Kibutsuji's Upper-Rank forces, we see glimpses into the past, including Akaza's tragic life as a human.
Tanjiro is pushed beyond his limits, leading to him unlocking the "Transparent World" technique, which he recalled being shown by his father years ago. As the name describes, when the technique is activated, Tanjiro sees the world as if looking through an x-ray. The flow of breath and blood and muscle contractions are there for Tanjiro to analyze as his ability to predict Akaza's moves and evade his attacks increases dramatically.
Tanjiro Seeing the Transparent World
Akaza -- the Upper Rank 3 Demon -- demonstrates his frightening Destructive Death technique, reminding Tanjiro of their previous battle when the Flame Hashira, Kyojuro Rengoku, died. As Akaza bombards Giyu Tomioka with a flurry of attacks, he manages to snap the Water Hashira's sword and, if not for Tanjiro's intervention, could have landed a killing blow too. One of the Upper Rank 3 Demon's abilities allows him to sense an opponent's fighting spirit, making it easy for him to dodge. However, to reach the Transparent World, Tanjiro cleared his head of hatred and anger, eliminating a detectable fighting spirit.
The battle seems to go the way of the Demon Slayers as Tanjiro gets the better of Akaza, cutting off his head using Hinokami Kagura, but the resilient Demon hangs on, quite literally, by clutching onto his head and attempting to reattach it. While Giyu's quick thinking prevents the Upper Rank 3's plan from happening, the now headless Demon fights on, much to everyone's surprise. Having reached his limit, Tanjiro is easily knocked unconscious by Akaza, and Giyu throws everything he has at combating him.
Akaza's Tragic Past, Revealed
As has become a staple within Demon Slayer, we begin to see glimpses of Akaza's past as visions of his loved ones start to appear in his mind. Though his body continues to fight on, Akaza struggles with a mental battle when his human memories begin to come back to him. Akaza, known then as Hakuji, suffered from a young age being forced into a life of crime to provide for his ailing father. Following Akaza's numerous run-ins with the magistrates, his father decided to take his own life so that his son could try to live respectably.
Angered and unable to live up to his father's hopes, Akaza rebels against the society who left his family to rot until a chance encounter left him completely changed. Taken in by a man named Keizo, who runs a student-less dojo, Akaza is won over by his strength and kindness. Akaza spends the next three years caring for Koyuki, Keizo's sickly daughter, while also training under her father. The three grow incredibly close, with Akaza and Koyuki even planning to wed, so when a neighboring dojo spitefully murders them, he is left a shell of himself.
Following a vengeful rampage against the ones responsible for Koyuki and Keizo's deaths, Akaza meets Muzan, who subsequently turns him into a Demon. As Akaza's internal struggles continue, Tanjiro regains consciousness to join Giyu in fighting him. For a moment, it appears as though Akaza will regrow his head, giving into to the Demonic part of his mind, but a final plea from Koyuki sees him fall to his knees and accept defeat. Akaza cries in Koyuki's arms, apologizing for failing to keep his promises to her as she forgivingly cradles him, seemingly joining him in a flame soaked afterlife.
Kanao's Rage Towards Doma
Meanwhile, Kanao faces off against the Upper Rank 2 Demon, Doma, who just killed and absorbed Shinobu Kocho -- the Insect Hashira. Incensed over her adoptive sister's death, Kanao taunts Doma as he feigns grief after learning of Akaza's defeat. She mocks his inability to express genuine emotion and reveals that Kanae Kocho -- the former Flower Hashira -- felt sympathy towards Doma because of it, causing him to lash out at her.
Kanao's impressive speed, keen eyesight and Flower Breathing technique enable her to successfully dodge and counter Doma's moves. The scales of the battle slightly tip towards Doma after he momentarily gains the upper hand by stealing her sword, but Inosuke exuberantly bursts in to level the playing field. True to type, Inosuke's boisterous claims of impending victory take a more serious tone when he learns of Shinobu's death from Kanao.
Inosuke Remembers His Mother
Inosuke's Beast Breathing technique catches Doma off-guard, especially after the Demon Slayer demonstrates his ability to instantaneously dislocate his joints, elongating his reach. As their clash rages on, Doma senses a familiarity about Inosuke and believes they've met after removing the Demon Slayer's signature boar mask. Doma finally realizes that he saw Inosuke as a baby and reveals he killed his mother.
Doma explains that Kotoha, Inosuke's mother, was in an abusive relationship and turned to Doma's false religion for sanctuary. While telling the story, he mentions a song that Kotoha sang to her son, sparking a memory for Inosuke. Claiming he didn't intend to kill her, Doma reveals he had no other choice after she learned that he was a Demon. A fleeing Kotoha knew she would die and, in an attempt to protect Inosuke, tossed him off a cliff into the river below.
The volume closes with Doma goading Inosuke over his mother's unhappiness and eventual death. However, Inosuke is thankful he caused him to remember his past, now reveling in the opportunity to exact revenge against the one responsible for killing his friend and mother.