As Giyu readies to fight Akaza once more, he realises the severity of the situation. His body's has reached its limit, his senses are failing, his body is numb, and the only thing keeping him up is his breathing. He knows a demon's body has no such limits, calling it a miracle for him to continue battle despite the heavy toll on his own. Giyu now focuses on protecting the unconscious Tanjiro, resolving to never let friends or family die on his watch again, knowing Tanjiro would do the same.
The woman's spirit grabs Akaza, telling him to go. Akaza tells her to let go, asking who she is. She tearfully begs for them to go to the other side, he only responding that he must kill Tanjiro and Giyu. When asked why, Akaza only answers he must get stronger. When she asks why he needs to get stronger, he answers "Because if I don't, I won't be able to bring back the medicine for Dad".
Akaza delves into his past. He was known then as Hakuji, an eleven year old boy who stole money for his father's medicine. One fateful day, he was caught, beaten and given tattoos to mark him a thief. The village's magistrate warns the boy his hands would be removed the next time, only for him to say "You cut them off, I still have my feet". The magistrate tells him the beatings he received would cause a strong man to become numb, calling him a demon child for being able to handle it. The boy tells him to continue with the moniker, saying he was born with fangs. After his beating and threats by the authorities, Hakuji walked home until a man informed him of terrible news. His father had heard he was caught and hung himself in shame. Hakuji went to the cemetery, reading a letter written by him to read after his death. His father wrote to him, "Dear Hakuji, live an honest life, you can still turn over a new lead. I don't want to live off money that has been stolen from other, I'm sorry for being a nuisance". After reading the letter and finding his headstone, Hakuji tearfully grabs it and grieves his death. He asks how his father can make peace with such people, finally cursing this world "can fuck right off".
Hakuji recalls his beatings for stealing money and how he could endure anything for his father, no matter how severe. He wonders why he had hung himself, declaring he would die for him. Filled with rage, he went back to the village and savagely beat seven men unconscious, all while saying his father never hurt anyone, he didn't bother him and he didn't need to apologize. Afterwards, a martial artist came by, drawn by the news a boy was about to be killed, instead finding said boy had beaten the seven armed men barehanded. Amazed at this feat, the man cheerfully asks if he would like to be his student, only for the still hurt Hakuji to threaten him back. The man notices his tattoos, calling him out for being a criminal banished from Edo. He happily takes a stance, and Hakuji charges forward to attack him, only for the man to rapidly beat him unconscious.
Later on, the man takes the awaken Hakuji for a tour of his dojo. He introduces himself as Keizo, a master who teaches the bare fisted martial art called Soryuu. However, he doesn't have a single student, making his living off handyman work. Keizo asks for the boy to care for his sick daughter, a task his wife had killed herself for due to its exhausting nature. Hakuji asks why he would leave his daughter with a criminal, only for Keizo to cheerfully remind him he beat up said criminal. Keizo's happy demeanour reminds Akaza of why he hates Tanjiro so much, because Tanjiro reminds him of Keizo, a figment of his boring and worthless past. As he continues to call his past worthless, he reaches the memory of when he first met Koyuki, Koyuki's sick appearance reminding him of his own father. As Keizo goes away to work, he leaves the two together. Koyuki asks if he is hurt, seeing his injured face.
Akaza curses his human life, remembering the promises he maid and failed to deliver. "I will cure you, protect, help you". He declares his life worthless, filled with empty promises.