Traitor | KNY FANFIC

A change in heart

Rui felt his life flash before his eyes as he felt the burning nichirn blade cut through his neck. Never once in a million years did he ever thought that this would be the way he would die, at the hands of two siblings whose familial bond is stronger than the ones he 'had' with his 'family'. His family....

Suddenly all of his human memories came flooding back into his head; he had two loving parents who cared for him despite his weak body, a warm house they all used to reside in, all up on top of a hill. One night, a demon no other than Muzan Kibutsuji, came and offered him a chance to live longer and finally be rid of this terrible illness that has been plaguing his body since birth. Rui foolishly accepted, not knowing that behind that caring facade laid a monster who preyed on innocents for centuries.. When his parents found out about him becoming a demon and eating innocent people, they....

Rui immediately unattached his head from his body before the demon slayer could cut his head off, his body laying motionless on the forest floor. Swiftly attaching his head back onto his body, Rui used his powers and made the threads that held Nezuko disappear, watching as the demon slayer ran to catch his sister.

What was happening to him? Why is he doing this again?

Gripping on tightly to his head, Rui stared at the demon slayer as he tried to get up to protect him and his sister, but couldn't to no avail. Rui felt pity for the two siblings, having to put up with this entire mess he created in the first place. He also felt pity for those he has killed, mistreated, and left out to die in the sun...But why?

Holding his hands up high, Rui surrendered to the two siblings. The demon slayer looked up at him in shock, his sister wondering if this was yet another trap to separate her from her brother.

"I'm...sorry for all of the trouble that I've caused. I know I can't bring back the people I've killed or made suffer, but I would like to atone for my crimes by offering my assistance up to the Demon Slayer Corps," Rui said in a hesitant tone, fully knowing the price he's going to pay for betraying his kind.

Tanjiro didn't know how to respond. One second this demon was trying to kill him, now he's surrendering and asking for redemption. Tanjiro could tell he was sincere in his apology, his scent changing drastically from earlier. He could also smell fear coming from him as well, alongside a mixture of both longing and betrayal.

"Please...forgive-"

Tanjiro caught the sight of Giyuu coming at Rui with his nichirn blade right out the corner of his eye.

"Rui, watch out!"

Rui quickly turned around and came face to face with the Water Hashira's sword, jumping back slightly as his head was nearly decapitated by the man. Shielding himself with his arms, Rui closed his eyes tightly and waited for the Hashira to attack him again. Hesitantly looking up, Rui noticed the demon slayer grasping on tightly to the Hashira's haori, looking up at him with a pleading expression on his face.

"Giyuu-san, don't!"

"He's a demon, Tanjiro, and a member of the Twelve Kizuki," the Water Hashira, Giyuu, responded in a cold tone.

"But he wants to change, Giyuu-san! Just take a look at him!" Tanjiro exclaimed as he gestured over to a shocked Rui, "I can sense it. Just please, trust me...let him live..."

Giyuu looked over at the demon with an annoyed expression on his face. Yes, he know he broke a major rule of the Demon Slayer Corps by sparing Nezuko Kamado's life, but sparing the life of Lower Rank Five...

"Do you regret everything you've done?" Giyuu asked the demon, his hand still gripping on tightly to his sword handle.

The demon slowly nodded, "Yes, I do. I know there's nothing I can do to bring back the lives of those I've took, but I'm willing to atone for my mistakes and take full responsibility for everything that has happened..and I'll help out in the fight against that man!.... Just please....don't kill me.."

Giyuu heavily sighed once again, as he has been placed in a very difficult position. On one hand, he did trust Tanjiro and his instincts. If he can tell Lower Rank Five isn't lying, then he should trust the kids gut. Unfortunately sparing the life of this demon comes with a lot of cons; he's killed people, works (or used to) for Kibutsuji, attacked and killed several of his comrades, sent his family after them, and not to mention Shinobu and her Tsukugo, Kanao Tsuyuri, were here too...

He's never going to hear the end of this...

"Tanjiro, grab both Lower Rank Five and Nezuko and run. Both Shinobu and her Tsukugo, Kanao, are here on this mountain too. They won't hesitate to kill any demons in their paths," Giyuu warned as Tanjiro nodded, grabbing both Rui and Nezuko by the hands and running deep into the woods.

As the trio further descended into the woods, Tanjiro felt someone attempting to behead him. Accidentally letting go of Nezuko's hand, Tanjiro frantically turned around and noticed a girl with a white cape charging at Rui with a sword.

Rui stopped for a few seconds before using his treads to safely restrain Kanao, motioning for Tanjiro to go after Nezuko. Suddenly he felt something hit him across the back, pinning him to the ground.

"Moshi moshi," a sickly-sweet voice called out as Rui hesitantly looked up, noticing it was a woman with a butterfly-like haori hovering over top of him, "Look what I got here, another demon!"

Rui could hear the sound of the other girl freeing herself from his trap, picking up her sword and chasing after both Tanjiro and Nezuko. Wait, were these the two demon slayers that Hashira was talking about?

"My, my, you look just like the other demon I had just killed earlier," the woman said as she unsheathed her sword, "Too bad she didn't last long against my poison. It was such a shame... Oh well, time to put you out of your misery now!"

Rui's eyes widened at the mention of his fake sister. Like the rest of his family, Rui regrets everything he's done to cause them any harm. If he had the option to turn back the clock and undo all of the damage he's caused, he would do so in a heartbeat.

But the fact that Kumo-oni Ane died mercilessly makes Rui both want to scream and cry... So Rui did, which caused Shinobu to grimace in disgust.

Before Shinobu could lay a hit on Rui, a figure jumped out at her, causing the Insect Hashira to stumble back a bit. Giyuu helped Rui up and looked at Shinobu with a disappointed expression on his face.

Nezuko and Tanjiro quickly ran back up the heel with Kanao on their tail, the latter having a kasugai crow on her shoulder.

"Don't attack or kill a boy with hanafuda earrings, a girl with a bamboo muzzle, and a boy wearing a white haori with spiderwebs on them. They are to be bought back unharmed to headquarters for a trial."

     Shinobu looked at the crow in confusion before switching her expression to a more cheerful one, "Oh, that makes a lot of sense! Kanao, you know what to do."

Kanao nodded as she knocked Tanjiro out with her sword handle. Rui and Nezuko looked at each other in complete shock before both of them got knocked out as well, everything around them fading into black.