Mount Natagumo was the residence of five powerful demons, these demons acted as a fake family. This facade of a family was all designed and planned by the 'youngest sibling', Rui. Rui had a desperate desire to have a loving family after his previous life as a human, he would take any innocent human that trespassed on the mountain and turn them into a demon using Muzan's blood. He would viciously modify their bodies and give them powers to fulfil the family's spider theme. He had formed a family of a Father, a Mother and two older siblings. No matter how hard he tried, the family just couldn't be perfect, it couldn't live up to his desolate desires. Rui was the youngest sibling, everyone was supposed to be protecting him, yet he found himself constantly outclassing his entire family. Regardless he kept his family around, to imitate the warmth a real family would have. Mount Natagumo was his home, and these demons were his 'family'.
The Demon Slayer Corps created the Mount Natagumo mission after several deaths on the mountain. The Corps were aware of this fake family in Mount Natagumo, however, they were unaware that one of the demons was a Lower Moon. They severely underestimated the strength of the demons. They sent Kanoe and lower ranks to handle the demons. They were shocked when half of the originally sent slayers were reported to be dead less than two hours after the mission's beginning. They sent reinforcements only for mortality rates to rise, finally once a Lower Moon was reported to be on the mountain, they sent two Hashira. When the Hashira arrived at the scene, three out of the five demons had been killed. Kaze and Asumi were the only two to defeat any of the five powerful demons.
Eira was slowly making progress towards the dark crimson aura so vivid in her mind, with every step she took closer to it, the more intense the frightening rage that radiated off the aura became. It was her first real fight in so long, after all the training, after the three months they had taken to improve themselves. Eira snapped back to reality, she stared forward at the moonlit path. Eira's legs stopped, and about 10 metres in front of her, a shadowed figure stood. Eira's heart pounded, how had she not realised this person was right there? Eira sighed and grabbed the handle of her sword, suddenly Eira's heart dropped and she came to a realisation. The reason she hadn't realised this person was because they didn't even have an aura. Where the figure stood, Eira couldn't sense anything, as if no one was even there.
"Impossible… Why can't I?..." Eira gulped with confusion, she continued to walk towards the moon-shadowed silhouette, she was much more cautious now that she had realised there was something off. The figure slowly leaned back, so far back it appeared as if they were floating at a 45-degree angle. Long hair dropped from their head, and the head eerily turned in Eira's direction. Eira's bones shivered and her blood ran cold seeing the disgusting mutilated face. She immediately recognised the facial features, the figure was no other than the girl who had passed out talking about spiders. Eira felt her stomach churning just from the sight of her face. The girl's skin crumpled like a piece of paper, cracks in her skin revealed glistening tissue beneath the skin. Drops of blood flowed out of her eyelids like tears, her mouth agape as her body followed the rotation of her head, the girl creepily floated above the ground as she slowly turned towards Eira. In a fraction of a second, a sparkle above the girl distracted Eira. Her eyes scanned the air above the girl, she caught another sparkle. She spotted extremely thin webs, attached to the girl's limbs and body. She was like a puppet, she was being controlled by those webs. Eira suddenly realised. No wonder she didn't have an aura, she was a lifeless corpse. Eira flinched as the corpse suddenly came flying at her, the corpse wasn't very fast, however, the horror movie-worthy face creeped Eira out. She dashed to the right. The corpse's arms flailed weakly as it rag-dolled through the air. Eira refocused and turned towards the girl's drooping body. She leapt towards the corpse and swiftly swung her sword through the thin strings above the girl. As the strings released tension, they bounced up, losing control of the lifeless body of the girl. The girl's body thumped onto the ground. Eira quickly kneeled beside the body. She rested a single hand on the girl's back and her eyes shot up at the string. She realised the strings slowly moving away. Retracting as if they were being winded back, most likely to the original source. Eira looked down at the girl's body and back at the strings.
Eira dug her shoes into the ground and launched herself off, she sprinted after the strings. Eira was forced to make sharp turns multiple times as the strings constantly changed directions.
After a solid 2 minutes of constant sprinting, the glistening strings finally led to a small moon-lit area. It was the exact area the crimson aura was radiating from. Eira held her sword tightly at her waist, as the strings darted from side to side, Eira's eyes locked onto a small area where trees circled. Eira closed her eyes to visualise the position of the enemies better. With just a single second she had it. Two auras fluttered in the small area, one was a soft blue the other was the infamous harsh red. She opened her eyes quickly again, she examined the area next, the scattered trees would constantly get in her way if she ran straight for the demons.
Without losing any pace, she dashed to the right and leant towards the ground, her footsteps had gotten quieter, as she tried to stay stealthy. Eira's eyes shot towards where the two auras rested at. She took a deep breath as she spotted a single demon sitting on a rock, with long white hair, a pale-white colour of skin facing away from Eira.
Eira almost immediately increased her speed, passing by trees with subtle movements to the left and right. She put all her force into one leg as she closed in on the small area, she thrusted herself into the air and closed the distance between her and the demon in almost an instant. After all, speed was Eira's speciality, manoeuvrability and speed, she had honed those skills to perfection in the three months. Eira unleashed her sword from the sheath and swung it at a quick speed at the demon, the sword glided through the demon's neck like a knife and butter.
An ear-piercing scream followed Eira's swift attack, as Eira's legs hit the ground she was faced by another demon. Eira was unable to stop herself from tumbling forward, her legs hit the ground and Eira launched herself right in the direction where the other demon stood. This was the demon that radiated the crimson aura. In the one second Eira was mid-air, her face pointed directly at the demon. The demon's eyes wide, he only looked like a small boy, bearing the same skin colour and red dot pattern as all the demons Eira had seen so far. As Eira looked at the demon, she was immediately drawn to the demon's eyes.
Eira's heart thumped as she read the interesting pupils that the demon bore.
"Lower Five"
The demon wasted no time, not even staying still for a second, a single thick white string shot out of the demon's finger, the string swung directly at Eira. Her mind screamed at her to evade the string, confusion overtook her, why would she be scared of a fragile string?
Regardless, Eira's anxiety was too strong for it to be wrong. She quickly twisted her body mid-air, she stabbed her sword into the ground and propelled herself to the left. She didn't lose sight of the demon while she landed on the ground. The demon took a single glance at his rotting Mother.
Lower Five, the 11th strongest demon of the 12 Moons, Rui. He possessed the ability to handle strong webs extremely fluently. He utilised his freakish strength to become one of the most brutal Lower Moons. His webs were so strong they could cut through rock with little issue, he would have no trouble dicing a single human to shreds in a matter of seconds, he was ruthless with little emotion.
"You killed everyone… You Demon Slayers. My whole family…" Rui's hands twitched as his voice spoke softly. Eira felt the soft voice strike her heart with fear, the atmosphere was intense, she felt as if the air was shaking as Rui's crimson aura got more and more dense with hatred, she had never witnessed an aura be so intensely violent. She couldn't take her gaze off Rui, who stood in a single ray of light, illuminated by the moon, he turned his head and stared at Eira, he pointed a single finger at her. Eira witnessed his hands changing from a pale white to a blood red, the colour slowly bled from his fingertips to his wrists, as his hands changed to the bright red, so did the strings attached to his fingertips. He had activated his Blood Demon Art.
Eira's soft blue eyes clashed with Rui's bloodshot red eyes. They didn't realise that they were two sides of the same coin, the loss of parents had driven both of their motives. They had both handled it differently, gone on opposite paths.
"Whatever. They were no family of mine, they were weak. Worthless." Rui spoke violent and insultful words in such a calm and soft tone, Eira's skin crawled with annoyance as Rui talked.
"Just because they were weak doesn't mean they aren't family." Eira had a strong stance on the topic of family, her one and only goal, to protect people close to her, sprouted from her love for her family. She thought of everyone close to her as her family, she thought of Asumi as a younger sister, and she had thought of Ali as a younger brother. It pained her so much when she wasn't able to protect him. Her entire well-being was shattered when she realised she had failed her goal of protecting those close. How could her goal be destroyed in such little time… The very fact that Ali was still roaming around as a demon further fuelled Eira's pain, that he would have to go through the torment of being a demon. Ali had become some sort of symbol of guilt and pain for Eira, he would constantly appear in her nightmares. If only… If only he actually died, instead becoming a demon. She didn't want to face him ever again.
"They didn't fulfil their roles, they were all older yet none of them stayed to protect me. The youngest, what use is a family that's weak?" Rui took a single step towards Eira, both of them ready to unleash their attacks at any time, it was only a matter of time before the brawl between them would unravel.
"A family isn't built upon strength or power, it's built upon love." Eira firmly stated, she gripped her sword as Rui kept taking slow steps. The tension between the two's ideals, motives and words was fierce.
"I've had enough of your nonsense." Rui snarled, he lifted his right arm and swatted the air as if swatting a fly. Several red strings fly from behind Rui, they tore through trees, stone and the Earth, slicing through like scissors and paper. The strings howled as they moved through the cold wind. Eira dashed to the right. She fully understood what would happen if the strings caught up to her, her whole body would be sliced into multiple pieces. A horrible vision of the event awakened in her mind. However, she also knew she had to find a way to get rid of the strings. Courage lit in Eira's heart, she took a deep breath and changed direction. Rui was confused when he saw Eira sprint right towards the strings.
"Does this demon slayer really think she can cut through my strings? Oh well." Rui tightened his hand, the strings that were attached to Rui's fingertips became much more straight and tight. Rui swung his arm again. Several trees fell as the strings continued to bring demise to all they touched, a domino effect followed as tree after tree crashed and toppled into another. Eira grunted and clenched her hands around her sword, she unsheathed her sword and increased her speed, she needed as much speed as she could to increase the strength of her swing. Soon Eira and the red strings were face to face. She had approximately 2 seconds before the strings would slice right through her body, 2 seconds to save herself from death. Eira took a deep breath, her sword was pointed towards the ground. Ice breathing. Third form. Rising snow. Eira's muscles burst with energy, adrenaline racing through her veins as she slightly leant backwards. Eira's sword swung upwards, clashing with all 5 blood-red strings.
Rui's eyes widened in disbelief as the strings broke one by one. He glared at Eira, her attacks so intense with determination.
Eira watched the red strings fall to the ground, she relaxed and turned towards Rui, digging her shoe soles into the ground, she saw the opportunity to cut his throat as he stood shocked. She was going to take it. She dashed forward, as she gripped her sword with both hands, she suddenly felt the crimson aura linger behind her. Her body clenched and her eyes ached, she shouted as she dropped to the floor immediately, a red string lightly grazed against her back, although only light, the string inflicted lethal damage. It tore through her uniform, a large cut distinct on her pale back as her thick jacket split into two. She was fortunate that she was able to sense the attack, if not… Her whole body would've been cut into two. She felt the sharp pain sting at her back, the cold air brushed at her fresh deep wound, which quickly swelled. Eira jumped to the right as another red string came flying down. She continued to evade the constant brutal attacks that Rui orchestrated. From every direction the strings continued to swing at her like bullets. Eira's back only stung more intensely with each second, she could feel the thick blood that poured out her injury and down her back.
"I have… to do something!" Eira's mind screamed as she rolled to the left. Rui gave her no time to rest or recover. Eira's mind raced, what could she do?! What form would get her out of this mess?! Eira's mind sparked with an idea.
"This is perfect… That form!" Eira's eyes lit up with hope. She gripped her sword and launched herself backwards as she evaded another lethal string. Eira's eyes were wide with hope, her blonde hair flowed in the wind. The strings continued to pressure her away from Rui. She had to get back up! She needed to fight back! A single face flashed in her mind, her father's face. The stern expression, the grey hair and down turned eyebrows. His face was so vivid.
"Mountain Gods give me strength…" Eira's hands wrapped around the coarse handle of her sword. "To defend myself, my friends and my family…" Eira's lungs filled with cold air. Her whole body raced with energy as she glared at Rui. The red strings raced at her face.
Ice Breathing. Eleventh Form. Winter's Conclusion