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Chapter Text

[Pic of Hoshiko above. Just  imagine her with plum-red eyes.]

A bit about  Hoshiko  before we start this chapter:

1) She looks 19 and has  eidetic  memory [photographic memory].

2) Over her thousand years of being alive, she has tricked many demon-slayers into falling in love with her, only for her to rip their souls out when they least expect it. The only ones she can't fool are ones with exceptional smelling and hearing skills, as they can detect her trickery and lies. 

3) As a human, she had the same deadly disease as her brother, who was older than her by a year. The doctor, who was the same one who treated Muzan, gave her the same type of medicine that he gave her brother. Muzan had killed the doctor when he saw that both himself and his beloved younger sister was getting worse instead of better, only to find out that they were actually getting better. However, since the medicine the doctor gave Muzan was just a prototype, Muzan couldn't go out during the day and  hungered  for human flesh. The same thing happened to Hoshiko, but her body had somehow changed, becoming stronger and her beauty only enhancing. Instead of  hungering  for human flesh, she  hungered  for human souls. She could go out into the sunlight and gained inhuman grace, speed and reflexes. Think of her as another Sebastian  Michaelis , only on a slightly tamer scale.

4)  Nichirin  blades don't really work on her.  The only thing it does to her is hurt like a b**** and slows down her healing.   Wisteria  flowers don't hurt her. She quite loves Wisteria flowers.

5) Muzan is actually quite glad that  Hoshiko  doesn't have the same restrictions as him, and refers to her as the perfect being.

6) She is a very excellent actress, able to fake an emotion or expression right then and there, the emotions and expressions looking genuine.

7) She can take a soul with either a kiss, a touch, or she can painfully suck it out.

~ ~ ~

[Her current outfit above. This pic doesn't belong to me.]

Hoshiko Kibutsuji neared the meeting place in Asakusa, Tokyo. Upon seeing her elder brother and his human 'family', she smiled and called out to him. "Nii-san!"

Muzan Kibutsuji looked for the source of the familiar voice and his eyes widened slightly when he saw her. His precious little sister. "Hoshiko!"

Hoshiko hugged her brother once she was close enough, and her smile grew as she felt him hug her back tightly. Both siblings breathed in each other's scent, basking in the presence of the other before finally pulling away. Muzan noted that the only visible difference about Hoshiko was that her black hair was much longer now, almost reaching the back of her knees. Half of her hair was up in a beautifully braided bun, secured by a beautiful hairpin. She wore a white hanfu dress that had black accents and red designs of red spider lilies at the skirt part of it. The dress was secured with an obi-like belt that was placed under her slightly more than generous bust. The obi-like belt had a red string flower at the left side and a red string wrapped around the obi-like belt to secure the red string flower on it. A beautiful, white jade phoenix pendant on a lavender beaded cord was attached to the belt. The sleeves of her hanfu dress was a bit feathery. Other than those obvious hints of Chinese clothing, she looked exactly the same as she always did.

[Pic doesn't belong to me. Her pendant ^ ^ ^]

"Nii-san, is this your wife and child?" Hoshiko asked as she looked at the pretty woman standing next to him and the child now clinging to him. Muzan picked up his daughter.

"Yes. Meet my wife, Rei. And my daughter, Yuki." Muzan introduced. Rei smiled at Hoshiko.

"It's wonderful to finally meet you. Tsukihiko told us so many stories about you, Hoshiko." Rei said, happy to have finally met the sister that her husband spoke so highly of.

"I hope they weren't the embarrassing ones." Hoshiko smiled as she covered her mouth with a long, hanfu sleeve.

"They weren't." Rei assured her. Then, she looked at Yuki. "Yuki-chan, say hello to your aunt."

"Hi Auntie." Yuki said with a shy smile. Hoshiko smiled and cooed at how cute Yuki was as the family of four began to walk through the crowd.

Yuki warmed up to Hoshiko quite quickly. Mainly because Yuki loved the sound of Hoshiko singing. Rei went ahead, something at one of the shops up ahead catching her eye.

~ ~ ~

Thirty minutes later, while both siblings were walking towards Rei, who was now walking back towards them, they both felt a hand on each of their shoulders.

Simultaneously, Hoshiko and Muzan turned their heads to glare at the person grabbing them, their identical slit-pupiled, plum-red eyes on full display. They had matching expressions of irritation on their faces.

They met eyes with a young boy wearing a scarf over his head and neck, along with green checkered haori over the demon-slayer uniform. The boy looked absolutely furious as he grabbed his sword, drawing it out a couple of inches, when...

"Daddy! Auntie!" Muzan and Hoshiko looked at Yuki, who was still in Muzan's arms, before Muzan turned to let Yuki see the demon-slayer boy. Hoshiko knew that Muzan only did that to stop the demon-slayer boy from attacking them. "Who's that?" Yuki asked as she curiously looked at the boy.

"We don't know, little one." Hoshiko said, her slit-pupiled eyes having returned to more human-like eyes in the instant she had looked at Yuki. Muzan did the same as he agreed with his younger sister. Hoshiko pat Yuki on the head gently, seeing how shocked the boy was from the corner of her eye as he stared at them.

"Is there something we can do for you?" Muzan pleasantly asked the demon-slayer.

"You appear to be quite upset." Hoshiko said, sounding genuinely concerned.

"Oh dear...what's wrong?" Rei asked as she approached them, smiling slightly when Yuki happily exclaimed, "Mommy!"

The demon-slayer boy covered his mouth in shock and horror when he saw that both Rei and Yuki were humans. He looked sick.

"Do you two know this boy? Hoshiko?" Rei asked the two siblings. They didn't notice how the boy jerked slightly at the name 'Hoshiko'. His teacher had told him something.

"There were confirmed rumors that Muzan Kibutsuji has a younger sister. The first female demon, Hoshiko Kibutsuji. However, the Demon-Slayer Corps has little to no information on Muzan Kibutsuji's younger sister."

He stared at the female demon, Hoshiko Kibutsuji. That explained why her scent smelled so similar to Muzan Kibutsuji's scent. 

"No. I just arrived back in Japan, and I've never seen him before." Hoshiko said, looking at her elder brother. "Nii-san, have you met him before?"

"No, not at all, imouto. What a nuisance. I don't know him at all." Muzan denied, sounding genuinely confused. "Perhaps he has...mistaken us for some other people?"

"Oh, really?" While Rei and Yuki were staring at the demon-slayer boy, Hoshiko and Muzan made eye contact, before the former's eyes darted to a male close by. Muzan quickly caught on and on a move too quick for the normal eye to see, raised a clawed hand and scratched the back of the male's neck. The only one who caught how the two demons communicated through their eyes was the demon-slayer boy, who's eyes widened as the male turned into a demon. The male turned to face his worried wife and attacked her, the hunger quickly taking over his mind.

In the ensuing pandemonium, Hoshiko grabbed Rei's arm. "Rei nee-san, this is dangerous. Let's move away." Muzan quickly agreed with her, gently ushering his wife away from the scene while simultaneously making sure that Yuki wasn't looking.

They looked back when they heard the boy shout, "MUZAN KIBUTSUJI! HOSHIKO KIBUTSUJI! WHEREVER YOU TWO GO...YOU TWO WON'T GET AWAY FROM ME!"

Hoshiko looked unconcerned. Rei covered her mouth slightly as she leaned towards Muzan. "Tsukihiko...what's wrong with that boy?" Rei asked.

Just then, Hoshiko and Muzan caught sight of the boy's earrings. Those hanafuda earrings. Their eyes widened, shock flashing through their expressions. The boy was too far away to see their shocked expressions, and did not see how their eyes turned back into their normal, slit-pupiled plum-red.

"I'LL FOLLOW YOU BOTH TO THE DEPTHS OF HELL...AND YOUR NECKS WILL FEEL THE EDGE OF MY SWORD! I WILL NEVER...FORGIVE YOU!" The boy continued shouting.

The two demon siblings remembered the last person who had those earrings. That man had stood over Hoshiko after severely injuring her, about to behead her and would've succeeded had she not started crying and pleading for her life, claiming that she had a baby at her home waiting for her and that she would change, not eating humans. That man had hesitated before allowing her to live. Muzan had admired his little sister even more for the quick and believable lie. He also hated that man, because that man severely injured his sister. And no one was allowed to hurt her.

Quickly getting over his shock, Muzan made his eyes turn more human-like and less demon-like, before he touched his sister's shoulder. Hoshiko blinked and with that blink, her eyes also turned more human-like and less demon-like. The two shared a look, before they both gently ushered Rei and Yuki towards their car.

~ ~ ~

"Daddy, Auntie, aren't you coming?" Yuki asked. Hoshiko smiled and gently pat Yuki's head.

"I'm sorry, Yuki-chan, but I have to go meet a few old friends first. One day, I'll come visit you soon, okay?" Hoshiko told her, and Yuki nodded, satisfied with that answer. Rei looked in between Muzan and Hoshiko.

Muzan answered his daughter with, "I've got to go to work. I'm still disturbed by what we saw earlier."

"Dear... Hoshiko...." Rei sounded worried as she looked at Muzan first, then Hoshiko.

"It's all right. We'll just ask the police to keep watch." Hoshiko assured Rei with a warm and reassuring smile. After a little more convincing, Rei and Yuki finally left.

The smiles fell off their faces once they turned around. The two demon siblings went into an alley, their eyes hooded. Three humans were walking towards them. The two demon siblings moved aside, yet the smaller human male from the trio of humans managed to somehow bump into them nonetheless.

"Oww... What's your problem?" the human male asked the two of them indignantly.

"..." Hoshiko's expression became dark, a mirror image of Muzan's. "My apologies." Both siblings said simultaneously. Then, they made to leave, only for Muzan to be stopped by that obviously drunk human male, who had grabbed Muzan's shoulder.

"Excuse us, but...we're in a hurry." Muzan said, trying to remain polite. 

Hoshiko took only one step forward when the drunk male said, "Hey, hey, those're some fancy duds you're both wearin'! And I don't like it! And with those pale faces of yours, you both look half-dead!" 

Hoshiko twitched, before she spun around and grabbed the male by the neck, her plum-red eyes flashing. Muzan watched as she didn't even bother to suck out the human's soul, choosing to instead painfully snap the human's neck. She threw the corpse to the wall with such force that it cracked the wall and didn't even turn around when the bigger man loomed over the two of them and shouted, "Hey! What're you doing to my little brother?!"

Hoshiko ignored the man, but Muzan's eyes narrowed at the blatant disrespect in the male's voice. Hoshiko watched the only other female in the alley shout: "He's dead! Ya-chan's not breathing!"

The bigger male gasped slightly as fury took over his face. He made to punch Muzan, only for the latter to kick the human male, sending him flying up into the roof high above them and killing him instantly. He then walked towards the terrified human girl, who was pressed against the wall the body of 'Ya-chan'. Hoshiko was crouching in front of her already, and Muzan did the same.

"Does our complexion look poor to you? Are our faces pale? Do we look sickly? Do we look like we're dying? Does it seem like we don't have long to live?" He questioned the terrified human girl. "Oh, no, no, no, no... we are an entirely different creature."

Hoshiko watched as he pushed his index finger into the head of the human woman. Her eyes were wide with wonder as she saw how his blood turned the human woman into a pile of flesh, before it disintegrated away. She had never seen him do that before, so he must've discovered this during the time she was away.

Then, Muzan stood up and snapped his fingers. Two demons appeared a respectable distance behind the two demon siblings. The other two demons were kneeling, their heads bowed.

"Bring us the head of the demon hunter with the earrings that look like hanafuda cards. Got it?" He ordered them.

"We will do as you wish." The female demon said. The female demon and the male demon disappeared.

"Should I go watch them?" Hoshiko questioned, and Muzan looked at her, nodding slightly.

"Just don't interfere with their mission. If they succeed in it, I may make them one of my Lower Moons." Muzan told her, and Hoshiko smiled slightly. 

"Now, what kind of sister would I be if I interfered with my older brother's orders?" She asked before disappearing.

Chapter Text

"You may think she cares, but that's just how my little sister works. She gets your trust, becomes your friend, maybe your lover, and the next thing you know, you're bleeding out on the ground as she rips you apart, just to take your soul. She can eat your flesh too, but she prefers souls. I've seen it happen so many times, and I've been proud of her every time." - Muzan Kibutsuji

~ ~ ~ ~ ~

Hoshiko stood on one of the walls beside the two demons, watching as they looked for their prey. They had noticed her, and upon quickly noticing how similar she looked to their master, they didn't dare to be rude to her. Her presence was accepted by the two demons as she listened to the bouncing of the temari ball that the female demon was playing with. 

BMP, 'Ting'

BMP, 'Ting'

BMP, 'Ting'

BMP, 'Ting'

Hoshiko and the temari demon watched the male demon as he used his own ability to track down the boy with Hanafuda earrings.

"Can you see?" The female temari demon asked the male demon as she continued bouncing her temari ball.

BMP, 'Ting'

BMP, 'Ting'

BMP, 'Ting'

"I can see, I can see...foot-prints. That's them..." The male demon said with a satisfied smile. Hoshiko saw the multiple arrows on the ground, pointing the same direction and in the placement of where their prey would've stepped. "They went around there... there are three of them. One of them is carrying a large box."

"How convenient...I wonder where they're all going." Hoshiko murmured to herself. A slightly strong night wind blew past them, making some of her long hair fly in the wind and her dress, along with her sleeves, sway. When it died down, her hair settled down, looking unruffled and perfect like always.

"How should we kill them, Mistress? Tee hee hee hee!" The temari demon questioned Hoshiko, bouncing her temari ball.

BMP, 'Ting'

BMP, 'Ting'

"Power swells within me..."

BMP, 'Ting'

"Because I just took the blood from your older brother."

The male demon looks at Hoshiko, awaiting her answer. Hoshiko smirked as she said, "How should you kill them?" She repeated the question. Her smirk grew just enough so that one could see her deadly sharp fangs. "Why, brutally of course! Make it a good show for me."

The two demons smirked as well, before all three demons followed the trail.

| Tamayo's house |

"A way to turn...demons back into humans...?" Tamayo was shocked by the question. "It does exist."

"!!" Tanjirou was visibly shocked. Hope filled his voice as he surged forward towards Tamayo. "Please tell me!"

Yushiro whacked Tanjirou away, visibly angered. "Don't get close to Tamayo!" The demon boy yelled.

"Yushiro..." A dark aura came from Tamayo, whose eyes were shadowed. 

"I just threw him. I didn't hit him." Yushiro said innocently. 

"Same difference!" Tamayo yelled, then told Tanjirou, "Every injury or illness...has a medicine or treatment. However...at present, making a demon a human again is impossible, unless you somehow convince Hoshiko Kibutsuji to give you some of her blood."

"What do you mean?" Tanjirou was confused, but he was starting to kind of understand something. 

"Hoshiko's blood is similar to her older brother's blood, yet different at the same time. Some of her blood, even a drop of her blood, can turn a demon back into a human, or it can make them stronger. It is all dependent on the demon's strongest desire. If they desire to become stronger the most, they will acclimate slowly and painfully, and also simultaneously changing into her type of demon, able to walk in the sun. If they desire to become human again the most, they will begin a very painful transformation back into a human. Sometimes, the pain is so much that those demons kill themselves to stop the pain. Rarely has any demon ever successfully turned back into a human and lived, because as soon as one successfully turns back into a human, they either get killed by another demon for food, or they are killed by Hoshiko herself for their souls." Tamayo explained all of this to Tanjirou, who took all this in with a serious face. 

"Besides, it'll be hard to get her blood." Yushiro added, making Tanjirou look at him. "Muzan Kibutsuji protects her very well, and Hoshiko herself is very dangerous since she's a different type of demon, meaning we don't know if her abilities are the same as any other demon, or if they are different."

"..." Tanjirou looked at them, disheartened.

"Nonetheless, we...want to establish a treatment. To do so, we need to study lots of demon blood. I want to ask two things of you. One...I want to examine your sister's blood. Two...I want you to get a sample from a demon with a high concentration of Muzan Kibutsuji's blood, as it's impossible to get blood from a demon closely related to Hoshiko. She keeps those demons close to her, or makes sure they're in a different country." Tanjirou looked a little shocked at Tamayo's words as she continued talking. "Right now, Nezuko is in a extremely rare and special condition. I understand she slept for two years, so her body must have changed during that time. Usually, if a demon made with Muzan's blood can not ingest human flesh or animal meat for such a long time...it will grow violent, without fail.

Yushiro didn't pay much attention to what Tamayo was telling and thought that Tamayo looked beautiful.

"But surprisingly, Nezuko does not have these symptoms. I think this miracle will prove to be the key." 

Tanjirou looked at Nezuko, and let her hold his right hand.

"The other task will be difficult. A demon with a high concentration of Muzan Kibutsuji's blood...means a demon close in strength to Muzan. It won't be easy to steal blood from such a demon. But will you still try?"

"Studying blood from many demons to make a medicine." Tanjirou began as he looked at Nezuko with a tender look in his eyes. "If that's the only way, I'll do it."

| Outside of Tamayo's House |

Hoshiko raised a hand to stop the two other demons from doing anything, and they did as told. They listened closely to the words being spoken.

"It will help...not just Nezuko, but lots of people, right?"

A moment of silence from the house. "Yes."

'That voice...' Hoshiko's eyes widened, then narrowed as she held out her hand to the temari demon, who gave her one of her temari balls. Without a second to waste, Hoshiko threw the ball in her hand towards the house with an immense strength. The Arrow demon aided in this attack and made it more lethal as the Temari demon threw another temari ball into the house.

"Kya ha ha! Just like you and Mistress said, Yahaba! A building appeared where there was nothing before!" The temari demon exclaimed excitedly.

Hoshiko's eyes looked around, before locking on to Tamayo, and a slow, dark smirk spread across the former's face, even as the latter's eyes widened in absolute fear.

"Seems like they've learned how to use the Blood Demon Art well." Hoshiko praised, though the smirk never disappeared. It only seemed to widen into a smile that showed off her fangs, and that terrified Tamayo even more. She had only seen Hoshiko smile like that once: to a demon that Hoshiko was personally planning on killing.

"And is the demon slayer with them? What does this mean, Mistress?" Yahaba asked Hoshiko, who was now standing a few feet behind them. Since he saw that Hoshiko was deep in thought, he turned to the other female demon. "But still, Susumaru...the way you do things is childish...and impetuous, but most of all, messy. My kimono got all dirty. Tch!"

Susumaru waved away his words. "Hush. Thanks to my temari ball and Mistress's help, we found them right away. Great! More time to play. And your kimono isn't dirty. You're too fussy."

'A temari ball! They could smash up the house just by throwing that ball?!' Tanjirou thought, horrified as he saw Susumaru hand a ball towards Hoshiko when she walked forward.

"As much as I'd love to kill these people, Susumaru...Muzan nii-sama would not appreciate my interference. I'm only here to observe, and see if you are both worthy to be promoted." Hoshiko said, even as her gaze went back to Tamayo. Then, without a word, Hoshiko bent her knees slightly, and jumped up into the air, curving her body backwards in the air, before landing safely on her feet a safe distance away.

Then, she watched Susumaru and Yahaba began to use their abilities to try and kill the occupants of the house. Her attention was mainly on Susumaru though, watching as the female demon taunted the demon slayer. She couldn't help but snort a bit when Susumaru proudly called herself one of the Twelve Kizuki.

Hoshiko's plum-red eyes narrowed as the demon protecting Tamayo threw something at the demon slayer, aiding the demon slayer in dodging the attacks, and in locating Yahaba. 

The corners of her lips twitched upwards as the demon slayer assumed that Susumaru and Yahaba were truly part of the Twelve Kizuki, demons that were close to her elder brother,  and promised Tamayo to get some of their blood to her.

Hoshiko looked over to Yahaba as he said, "Mistress. Isn't that one over there Tamayo...the runaway?"

"Indeed she is. I'll be dealing with her later, along with her little pet." Hoshiko said, her voice just loud enough for him to hear. A small smile formed on her face as she spoke.

As Hoshiko continued watching everything play out, that little smile stayed on her lips, even when Yahaba was beheaded by the demon slayer. She watched the demon slayer panic for a little bit, before he used techniques to stop himself from getting any serious injuries. Her eyes went to Susumaru, who was slowly being overpowered by the younger female demon. 

Hoshiko's eyes widened by a tad, and soon, interest shone in her eyes for a brief second before it disappeared, being replaced by amusement and annoyance, as she heard Tamayo start talking to Susumaru, trying and succeeding at getting under the latter's skin. 'So she could still manipulate someone with her words-- Ah, she's just using her Blood Demon Art. How disappointing.'

"Shut up! Shut up, shut up! They aren't that weak!" Susumaru yelled, fearful and angered at the same time. "Their abilities are fearsome! They're stronger than anyone!"

Hoshiko said nothing, not showing just how pleased she was to hear what Susumaru said, pursing her lips as she watched Susumaru to see what she would say next.

"Both Kibutsujis' are..." Susumaru widened her eyes and slapped a hand over her mouth. Hoshiko's eyes went cold. 

"You said their names, thus triggering the curse. I pity you...but I had no choice." Tamayo said, pity in her voice. Hoshiko jumped down from where she had watched the entire thing.

Susumaru ran over to her, pleading,"Please, forgive me! Please, forgive me! Please, forgive me! ...forgive--" Her voice was cut off as she saw the cold and unforgiving look on Hoshiko's peerlessly beautiful face.

The demon slayer watched, shocked, as Susumaru doubled over in pain. Then, mutated arms emerged from Susumaru's mouth and torso.

The demon slayer noticed Hoshiko watching apathetically as the mutated arms utterly destroyed Susumaru. Hoshiko noticed his staring and a smirk formed on her lips as she walked over to him and crouched down to grab his chin.

"It would be so...easy...to kill you right here and now..." Hoshiko began, making the demon slayer tense up. "However, because you put on a very amusing play, I will spare your life...just this once. When we meet again, I will have your head."

She let go of the demon slayer's chin and looked at Tamayo, before smirking. "As for you...expect a visit from me soon. You know fully well that you can not escape me." With that, she turned around as she raised a hand, the long sleeve falling down to reveal a white arm and hand. Her slender fingers were each tipped with sharp nails, which was a dark purple on the bottom that faded to a light purple towards the tip of her nails. 

She snapped her fingers, and the sound of a biwa being played echoed through the empty courtyard before a shoji doorway appeared in front of her. The moment she walked through the open doorway, it faded out of sight as the sound of the biwa was heard once more.