Tomioka-san, where is she?

Act one; Figuring it out

Tomioka Giyuu was standing out the front of the water estate entrance, blocking Kocho Shinobu, one of his comrades and workmates from entering the villa which seemed to always keep the blinds closed or windows boarded up. "Tomioka-san, why won't you let me in?" The woman's voice was honey coated but you could tell she was starting to get irritated.

"Why do you need entry?" Tomioka shot back, he was in a bad mood from before, he had had an argument with his younger sister and took one step out of the villa to come face to face with a human sized pest. "You have the butterfly mansion, go there."

"Ara ara, Tomioka-san why are you being so mean today?" the girl asked, she had come over because she had smelled what she thought to be a demon's scent, it wasn't Nezuko's like it normally was. "I came over to see if you were okay, I believe a demon other than Nezuko has gotten into the area."

Tomioka looked at the woman then looked back into the villa, it was very dark, the only light was from the candles which he had set up a few weeks ago. "My villa may look like an ideal place to hide a demon but I can assure you there are no demons in here." Tomioka's face was practically a wall of stone covered in skin, his eyes icy and hard.

With a sigh the black-purple haired female nodded, taking a step back "Alright Tomioka-san." with a shake of her head she turned and walked over to the bridge that divided the water estate from the rest of the demonslayer corps HQ, the running river below the bridge was raging as usual. "But if I find out you are hiding another demon, Tomioka-san, I'm afraid we'll have to kill them."

Tomioka glared at her "and what if that demon is like Nezuko?"

"Then, we'd have to see what the master says." with that the insect hashira crossed the bridge, leaving behind a very upset Tomioka Giyuu.

Tomioka sighed and walked back inside to be met by a girl with long black hair, deep blue eyes which fit the description of a 'sirens eye' shape. The woman had two large, sharp fangs on the top and bottom of mouth, blood all around her full lips, contrasting with her paleish skin. "Shi, did you find the demon that broke in last night?"

For some reason demons could get in and out of the wisteria trees at a certain time of night, Shi even though being a demon she hadn't hurt anyone and the master already knew of her existence, she would patrol the HQ area when the Hashira's were away, injured or too exhausted to move. Because of this the girl got a good feed almost every night.

Unlike Nezuko, shi ate demons as well as normal food, never once had the demon attacked a human with the intent to eat them, she has attacked people before though, mainling for training when she was younger and when they hurt her elder brother.

"Hai! Ani I did, it was the current lower moon six, he didn't have any particularly strong demon blood art and seems quite sloppy.." the girl hummed, thinking back to how her fight with the demon was over in the matter of minutes instead of an hour or two.

Giyuu laughed, shaking his head. They had already forgotten about the argument by now. "That's probably because you're most likely as strong as the lower moon one now." Giyuu watched as the girl's eyes lit up, she was happy to be able to be that strong at least, after twelve years of eating demons she had finally managed to get up to the strength of the lower moon one.

Even if Giyuu's calculation was off and she was as strong as upper moon five the girl was practically shining with glee, this made the water piller smile. "Go wash up and I'll take you to the city for a night out." The demon jumped up, rushing away to go bathe with the help of the few Kakushi which wore blue instead of black uniforms, something the master had made available for them so Shi didn't get confused, all Hashira's personal kakushi which live on site only wear the colours given to them.

Giyuu sighed and looked at one of the closed blinds from the inside, it did look like he was housing a demon from the outside (not that he wasn't) and people other than Shinobu might start getting curious, if Shinazugawa Sanemi or Oba nai Iguro find out about her they'll do their very best to kill her just like how they did with Nezuko.

Another sigh left his mouth as he headed to the second bathing chamber and walked in, stripping himself down and getting into the cool water.

Shi had been turned when she was four, Muzan himself had turned her. After their elder sister had died protecting them from a demon Giyuu was called crazy for explaining what had happened that night and was sent away to go to his distant relatives for mental treatment, he ran into the mountain, holding his baby sister close to his chest while running, they both almost died due to hypothermia.

Luckily Sakonji Urokodaki had found them and decided to take them in, teaching Giyuu how to be a demon slayer while he raised a innocent, unbeknowing Shi who didn't need to know about the world of demons around them, that was until the girl turned four years old and met Muzan Kibutsuji who turned her.

The man had injected his blood into a four year old girl after she had bumped into him and left her for dead, never expecting her to be able to live through the transformation at such a young age. When she got home that night, she came home, covered in her own blood, fangs on display, hair as red as blood and eyes bright purple, she was a sobbing mess. No one of the four demonslayers (Three in training and one retired old man) was expecting this to happen to a four year old child.

As the years went by she grew up learning to fight, being fed demon meat and human food, slowly her body's wants of eating human flesh vanished and it started to crave demon flesh, her body had also been growing with her as she aged unlike most demons who are stuck at the age they were turned. Though she wouldn't be affected by wisteria she could be burned by the sun, which was a worrying discovery for the four demonslayers who lived with her.

When Sabito and Makomo passed away Giyuu had spiralled into a depression while Shi (who was being watched by Urokodaki at the time) went on a killing spree, killing and feasting on any demon she could find she she could take their strength so she'd be able to protect her brother. Now, in the current day she is beside her brother on every mission, wearing half of their sisters and best friends' haori's joint together.

Tomioka stood, wrapping a towel around his waist and walking off to his bedroom, getting dressed in a deep purple, almost black kimono, with a wisteria purple waistband/ribbon wrapped around the middle to hold it in place. He put his hair up in a simple ponytail, which his sister would most likely change into a bun for him.

Tomioka Giyuu, the water piller was not one to go out other than on missions but there was a rare occasion where he would and it would always be right at sundown with a girl who used a red, laced parcel. That girl was his younger sister, not that anyone would ever (hopefully never) find out about.

Shi entered the room in a very much matching kimono, her hair up in a tight bun (which was how Tomioka's hair would be in a minute) and a red laced parcel in hand, socks on both their feet as they walked to the door, slipping on the traditional wooden sandals with small stilts on the bottom to keep the soul and the kimono off the floor (These shoes are called Geta's). Shi did the same as her elder brother who opened the door for her.

She took a few steps out into the light, opening the lance parcel and pulling it above her head, blocking all light from touching her in seconds. "Would you like me to hold it for you this time?"

"No thank you ani."

"Just let me know."

With that the Tomioka siblings walked off, a smile on both of their faces.

However back in the butterfly mansion, Shinobu was rigged, there have been no demons sneaking in lately, no demon attacks or even attempts against the master like there had been for the past two months after the demons had discovered the opening in the wisteria tree border, they had no idea where that gap was and no way to fix it, but something or someone was hiding in the darkness and protecting the master every night before one of them could get there.

At first the faint smell of two demons tangled together so the hashrias thought it may be Nezuko but after Tanjiro and the rest of his team had gone on a week long mission, with Nezuko they had found out it was a different demon.

Shinobu had come to the conclusion that Tomioka was either a demon or was hiding one, but demons can't go out in the sun, maybe the master gave him a petal of the blue spider-lily- no that just seemed stupid, why would the master do that for a demon? Even if they're a demonslayer.

The only second reasonable thing would be that Tomioka was housing a demon which didn't have a proper scent, or maybe the water piller was masking it with his own smell, even Tanjiro said Tomioka wasn't hiding a demon, but something seemed off, maybe Tanjiro was in on it?

Shinobu had called a meeting with all the hashira's (other the Giyuu) and was now sipping some tea she had prepared, the first three to come in were Tengen Uzui; the sound pillar, Kyojuro Rengoku; the fame pillar and Mitsuri Kanroji; the love pillar.

Next came Obanai Iguro and Shinazugawa Sanemi; the snake and wind pillars. Sadly Gyomei Himejima and Muichiro Tokito (the stone and mist pillars) couldn't make it to the meeting as they were away on a mission together- or just spending some father-son time, who knows.

"Okay, why did you call us here bug breath?" Shinazugawa asked, pissed off that he was brought here from training to deal with something to do with Tomioka.

Shinobu hummed "Shinazugawa -san, if you don't want to be here you don't have to~" the woman with purple tips in her hair cooed, already pissed off by the white-haired male, whom just huffed in annoyance. "Anyways, I've brought you here because you've most likely seen the changes in the attacks towards the master."

"Ah! Yes, they've stopped completely! Isn't it lovely?" Mitsuri asked, smiling brightly, everyone nodded in agreement- everyone but Kocho.

"Yes, that's the thing, they've stopped as if they never happened or as if someones guarding that area where they can get through, every night." Shinobu started, getting everyone's attention, now that they've had it spelled out to them they looked around the room, waiting for someone to speak up. "I believed it to be Nezuko at first, like we all did but after her and her brother's group left for a week, and still no attacks it occurred to me that it isn't Nezuko."

The air grew somewhat thick now, waiting for Shinobu to state her case.

"I think Tomioka-san is hiding a demon." The words fell out of her mouth like they had been slowly hiking their way up her throat like it was a cliff only to collapse and fall off when they hit the top of the cliff, falling off the edge into a sea of sharks.

"You think that the emo is hiding a demon?" Uzui asked with a hum, looking up from playing with the love pillar's hair, the three which sat together were basically a bunch of siblings. "Does he have a demon sidekick too? If so, he is flashier than I thought."

Shinobu's eye twitch in irritation "He has been hiding a strong demon in his house, from what a Kakushi (even though it was indirectly) at the water estate, lower moon six snuck in last night and no one can find him so he either died in the sun or was killed by someone or another demon."

"You think that Tomioka Giyuu; the most antisocial person you'll ever meet is hiding a demon and that it's at least stronger than lower moon six?" Shinazugawa laughed to himself at the idea "No way, how could he hide a demon if he doesn't talk to anyone? The demon would've eaten him alive already!"

Shinobu sighed, again.

"He doesn't talk to anyone, which makes him good at keeping secrets, since he has no one to tell, his estate's windows have been boarded off or are always sealed with curtains, the master is always calling him back after meeting to ask him about someone called 'Shi' and he only leaves on missions, to meetings or with a girl who hides her face with a red laced parcel." Obanai spoke up this time, laying on the floor, facing up at the roof as if peacing it all together.

"Those things don't mean he's hiding a demon! Maybe it's his lover!" Rengoku announced, being overly loud as always.

Mitsuri squealed "Tomioka-san having a secret lover?! That might just be what he needs to help him with his antisocialness!"

Shinobu was about to give up with these fools.

Even Shinazugawa was shaking his head now. "So, we have someone named Shi, who is most likely this lady with the red parcel and Tomioka who is hiding something from all of us, including the master." he hummed "What if the master knows the person, knows she a demon and letting her live, like how he's done with Nezuko?"

"Then that's just fine, I'm just curious as to what could make Tomioka-san be even more locked away than he was before he moved into the water estate." Shinobu hummed.

Act two; Tomioka-san, where is she?

Tomioka Giyuu was walking back across the bridge to the water estate, the group of hashiras watched silently from the tree's nearby. The man was half away, carrying a girl on his back who seemed to be fast asleep, drool running down her left cheek, you could just barely see the tips of her fangs. Tomioka threw the girl up onto his back more, getting a goran of protest from the sleeping girl.

"Shi, you need to wake up, I'm going to collapse.." Giyuu whined, literally whined, everyone froze, the honest emotion on his face made them stare in shock, a small gulp could be heard if you shared the same body as Shinobu, she could tell that the girl and Giyuu were related just by the facial features which they shared, cheek bones, eye shape, nose's, the girls lips were fuller than the males but that might just be from their gender differences.

"Tomioka-san has a sister.." She whispered to herself, watching as around three Kakushi dressed in the blue water pillar's estates uniform came running over, helping to get the girl off Tomioks's back and inside the villa, while Tomioka looked like he was about to collapse. From their positions in the trees they could hear everything being said, the girl who was on Tomioka's back was called 'Lady Shi' by the Kakushi.

Now that Shinobu took a second to look at her friends' faces she could see the shock on Shinazugawa and Obanai's faces, they clearly hadn't been expecting this turn of events. Mitsuri was beaming with joy, probably finding the demon adorable, Rengoku and Uzui weren't even paying attention and were talking about something random.

"Sir Giyuu, we've cleaned up the demon's remains.." A Kakushi who stayed around after the other two went inside spoke up, Tomioka standing up straight.

"And?"

"The lady killed it in one blow, she's much stronger now." the Kakushi seemed proud, and so did Tomioka. "I think she'll be as strong as upper moon four in another week."

The black haired man nodded "Thank you for the help, please go get some rest.'' The male walked inside while the Kakushi walked away to go back to his and his friends' building on the estate, no one left the water estate often and if they did it was under Tomioka's order no one else's.

Shinobu hummed "Shinazugawa-san, should we confront him at the next hashira meeting?"

"That's tomorrow morning." The man responded "do you think he'll even be there?" Tomioka looked pretty exhausted from his night out with that demon, something about it made the white man's heart race, just a little.

"He should be, if not we'll confront him in the afternoon."

At the meeting Tomioka did show up, this time with the girl clinging to his arm, no one knew why she was here or why tomioka looked like he had been crying for hours, they had left after the man had gone inside and now, seven hours later Tomioka looked well rested and like he had cried for two hours or more.

Shi walked up onto the area, where the master stood and stood beside him while her brother was sat, bowing in the line. "My children, I'd like to welcome you all." The man said, smiling at them all, looking them over "I'm sure you'd all like to know why the demon attacks against me have stopped and Tomi- Giyuu and I have decided it's time to tell you."

Said demonslayer stood and walked up, standing besides the master, something inside the other hashira's made them feel slightly jealous. "Giyuu Tomioka is the elder brother to Shi Tomioka; a demon who feeds on demon flesh."

Mitsuri gasped quietly. A demon who didn't eat humans but instead ate demons? She didn't see this coming at all, no one did.

"A demon who eats other demons?" Shinobu said bitterly, "So she is a cannibal?"

"Yes." Tomioka Giyuu, the water pillar said bluntly "much like how demons gain strength from eating humans, she gains strength by feeding on demons." The explanation was simple but somewhat shook the rest of the group to the core. "She got turned at the age of four."

They stared wide-eyed at the female who looked to be around fifteen years old "She looks like she's fifteen.."

"Her body continued to age until she hit fifteen which is when we discovered her blood demon art; reality morphing or commonly known as illusions." the words hung heavy in the air "she has been coming on missions with me for years, she even went to final selection with me."

"You're lying, half of that mountain is covered in wisteria flowers! She would've been trapped!" Shinobu yelled, the lie was clear.

"Wisteria doesn't affect her, the sun does but the flowers don't, she's able to go in and out of any wisteria protected area as she pleases." The master smiled, gesturing to the girl "From what I've heard she took lowermoon six out in one blow."

A shiver ran down the hashira's spins. "What if she eats a human?"

"She's grown up on demon flesh and has grown to crave that instead of human flesh." Giyuu countered, he was ready for almost everything they threw at him.

"Has she killed someone before? Hurt a human?" Shinazugawa shot back, he was honestly trying to get the water pillar to show more emotion again, like he had done last night.

"She has attacked someone before, not to kill-"

"To kill." The girl corrected her elder brother which had been cut off. "I attacked him to kill him ani, he hit you with a glass bottle." The girl's voice was cold and dripping with venom.

"- to kill him but not to eat him, she had simply lost control of her anger after he hit me." Giyuu corrected himself. "I stopped her from killing him but I doubt his spin will ever work again."

Something inside the other pillars twisted in fear, a teenage demon who attacked to kill anyone who hurt her elder brother, a demon who ate other demons flesh without blinking an eye, a demon who was able to take out a lower moon in one hit.

This demon was on their side.

"Now, everyone, can you leave the Tomioka siblings alone and stop spying on them in the middle of the night?" the master spoke, making the six freeze, they had been found out. "You are dismissed."

It had been a month since everyone had found out, Shi was constantly using her blood demon art now just to not be dragged away to a talk between the two female pillars about how attractive or gloomy her brother was. Tomioka Giyuu was on the couch reading a book with his sister's head in his lap, his hand tangled in her hair, he had been running her head for the past few hours.

The door flew open and Shi disappeared, now using her blood art to no longer exist on the couch without actually moving.

"Ara ara, Tomioka-san, where is she?"

Shinobu.