Demon Slayer: Kimetsu no Yaiba: Hinokami Flames

Chapter 16: Butterfly vs Spider

Through heavy amounts of pain, Tanjiro and Nezuko were able decapitate the Lower Rank Five Rui's head. Using the last amount of strength left, Rui's body socked Tanjiro in the face injuring his jaw. 

'I actually beat a Twelve Kizuki.' Tanjiro thought to himself. He then turned to see Nezuko on the ground unconscious. 'Nezuko! I have... to help... Nezuko!' He then crawls over to his sister. Rui was angry that he was defeated. He was about to die. "How did this happen? Did he cut through so many of my threads?! I can't even attach my head back on! Damn it! Damn it!! I'll kill them! Kille Them!!! I will kill those siblings!!" He then widened his eyes seeing how Tanjiro was checking on Nezuko's condition. He then sees Spider Mother. 'Rui tell me what is it that you want?' "I... I... I guess I wanted what they had. The true bond of a family.'

Elsewhere the daughter was running down the mountain in fear. 'I failed! I failed! That's all I do is mess up in my role!'

(Flashback)

Before she joined the spider family, she was a normal demon running from the demon slayers. She was cornered by a large house, and she was surrounded. Before any of them could strike, they look up to see Rui standing on the roof. "Little demon, do you want me to save you? The only price is that you obey my every command." "Yes!" she replied. "I'll do whatever you ask of me to do!" "Excellent." Rui then proceeded to slash the slayers into pieces. "Welcome to my family." She looks behind her to see a various of Spider Demons.

Inside the house, Rui begins to initiate the new family member into his family. "Through my blood you will properly become like us." He then drops a droplet of blood into a small bowl filled with liquid. "As a member of my family, I will now share with you my strength as I am one of "that person's" favorites." As she swallows the liquid, Daughter begins to experience pain. "And now, for the finishing touches." Rui rips off her face making her scream. Her appearance becomes similar to all the other demon spiders. "Congratulations." 

As they live life as a family, the daughters learn that they are not blood related. They begin to see Rui punishing Mother for disobeying him. She apologizes and will continue to play her role. Feeling tortured for too long, the Eldest Daughter plans to run away from the mountain the night Rui is summoned by Muzan. She asks her sister to join her to which, she agrees.

As they run down the mountain, Rui stands in their path. Wishing to survive, Daughter turns on her sister to avoid the consequences. "So, you put her up to this pathetic attempt?" Not getting an answer, Rui slashes his older sister and leaves her restrained on top of the house. "How disappointing." He turns to Daughter. "Come. It's almost sunrise." Daughter looks up at her sister one last time, before escaping into the darkness. The sunlight hit the eldest sister burning her to death.

(Flashback Ends)

Daughter still remembers that day very well. 'If I hadn't suggested we leave, then he probably wouldn't have slashed my face and caught that demon slayer's attention.' She then looks to see two slayers. One of them had bandages around her arms. It was Murata and Ozaki. They soon spot the daughter. "Demon!" Murata goes to attack, but Daughter uses her Blood Demon Art.

Acid Cocoon

She entraps Murata in a cocoon of silk that begins to fill with acid. He tries to cut through, but it's useless. "Don't bother! You can't cut free from this! The string bundles look soft but are hard to cut through. Acid will fill up from the inside and will melt your clothes off. And then you will become squishy, and you'll be my meal. And then I'll do the same to her." She points at Ozaki who's trembling in fear, but then shows a face of hope and relief. "Huh"