Chapter Text
It was late at night when Rengoku Kyojuro returned home from his mission, a bright smile on his face as he walked up to the estate.
As he approached he felt something was off, was the door open? Who would be up this late, and leave the door open at that?
As soon as he stepped in his door his ever-present smile dropped.
Blood, blood everywhere. Splattered on the walls, pooling on the floor.
His father’s half-dead body was lying on the floor, sword in hand, sake bottle smashed against the wall.
“Kyo- juro…” his father coughed out, lying in his blood.
“Father! Who did this to you?! What happened to Senjuro and Obanai? Are they alright?” Kyojuro panicked, kneeling next to his father and staining his uniform with his blood.
“Kyojuro, listen. The master- the master sent one of the hashira here to kill Senjuro and I. They wanted to blame Obanai and have you kill him,” Shinjuro said, reaching a shaky hand towards his son and resting it against his face.
“But why-“
“Because our family has morals, Kyojuro. They want to rid you of your humanity and make you a mindless slave for the master. That’s why I refused the hashira position, they would’ve made me kill innocent people. That’s why I started working with Ubuyashiki-san.”
“Then what do I do- how can I-“
“It’s too late for me, Kyojuro. I need you to know one thing. No matter what I said or did I was and always will be proud of you,” he says softly as his hand drops from his son’s face.
Before he could even comprehend what he was told he heard a sound, a muffled choking noise followed by a faint hiss in the next room, Senjuro’s room.
Rengoku bolted through the hall, almost breaking down the door when he entered.
A choked sob left his throat as tears welled up in his eyes.
“Brother! Obanai!”
Senjuro, his poor younger brother, was cradled protectively by Obanai. Senjuro’s chest had three huge gashes across it and his neck had two small puncture wounds, probably to look like a snake bite from Kabuamaru even though his fangs are much smaller than whatever they used.
Obanai however looked almost untouched. There were small scratches, scrapes, and a few bruises, including a particularly large one on the left side of his head. His largest wound however looked to be done with a precision and purpose that made Kyojuro grit his teeth in pure anger. Whoever came here, whichever hashira was sent, removed Obanai’s bandages and made his mouth scar longer than it already was.
He fell to his knees and reached his shaky hands out towards them.
He gently removed his brother from Obanai’s hold and into his own, his blood covering his already soiled uniform. Senjuro’s body was cold, his heartbeat long gone. Kyojuro’s tears flowed from his eyes and landed on his brother’s face, pain evident on his features as he lowered his forehead to touch his brother’s.
“I’m so sorry, Senjuro. I wasn’t strong enough, I couldn’t protect you.”
As he held his brother’s corpse and wept another figure entered the room.
“Oh my poor children, it seems like I’m too late,” Ubuyashiki said as he looked at the display. “But Obanai-san is still alive.”
Rengoku’s head shot up from where he was huddled, staring wide-eyed at the man in front of him.
“Ubuyashiki…”
“Rengoku Kyojuro. I would like to humbly apologize for the chaos and pain that being associated with me has brought to your family,” Kagaya bowed to the young man before walking towards Obanai. “However Obanai is still, just barely, alive. From what I can sense they used an old vial of blood from me and tried to make him a demon.”
“Your blood…”
“Ah yes, I suppose your father wouldn’t have had enough time to have told you. I am the demon king.”
“If you’re the- then why? Why would my father work with you? Why would he jeopardize our family like this?!”
“Because not all demons are man-eating monsters, the demons I create and raise as my own rarely kill for fun. And when they do… I take care of them,” Kagaya kneels in front of Obanai and places a hand on his head. “Rengoku, he’ll have to finish his transformation to stay alive. I can help speed up the process-”
“Then help him! I want no one else dying today!”
“...ok,” Kagaya moves the hand on his head to his neck and plunges a finger into his flesh transferring more blood into his system.
Obanai’s body started to convulse as Kagaya pulled away, fangs and claws growing, markings appearing on his body, and a snake-like tail growing where his legs used to be. Even Kabuamaru wasn’t safe from change, gaining the same strange markings as Obanai and merging into his body.
He started growing, hissing, and clawing the floor under him before his head snapped up towards Kyojuro and Senjuro’s corpse. He readied himself to pounce as Kagaya stepped behind him and delivered a swift chop to his neck.
“I thought you said your demons don’t eat people.”
“I never said they didn’t eat, I simply said they didn’t kill for fun. Besides that his transformation was a tedious one, he’s probably quite starved. But we have other matters to discuss now. What will you do now, Rengoku?”
“What do you mean?”
“Well, I doubt you’d want to go back to the demon slayer corp after they massacred your family. So what will you do now?”
Kyojuro’s tense shoulders sagged as he finally comprehended his situation. What would he do? His family dead, his friend a demon, and the corp he dedicated his life towards revealed to be corrupt. His entire mission: to protect the innocent, to protect his family, failed. He looked up at Kagaya, new fresh tears in his eyes.
“I… I don’t know.”
Kagaya looked down at the poor young man and with a small calming smile said, “It is the duty of those who are born strong to help those who may be less fortunate. That’s what your mother said that day, correct?”
“Yes.”
“Then you, as someone born strong, must continue to protect the weak. Even in the face of such tragedy. Kyojuro, would you like to become stronger, become a demon, and protect the innocent from the evil in the world? Human or demon?” Kagaya asked while holding a hand out towards Kyojuro.
“I will become a demon,” Kyojuro said, laying Senjuro’s corpse down and accepting Kayaga’s hand. “To protect the innocent. And burn away evil with the passion and determination of the Rengoku family!”
Kagaya smiles softly and stabs his fingers into Rengoku’s neck.
Rengoku slowly transformed into a demon as Kagaya grabbed his sword and the family cape from the living room and his father’s room. Once he returned he saw Rengoku holding Obanai’s still sleeping form waiting for him.
“Come along then. There’s not much time before sunrise.”