For the record, I also have this fic on AO3. It's under the same username and title and is a couple of chapters ahead :)
He found Akaza on a hill overlooking a large mansion with a tall wooden gate. Unfortunately, it looked as though he had been waiting for a while. He didn't look very bothered by it which was good.
"Hello! You're Upper Rank Two? We've never met! My name's Douma!"
Akaza merely glanced at his ranking and then back at the town.
Douma smiled politely. "And your name?"
He was ignored, as usual. Douma would usually push for an answer but it wasn't as though he actually needed it.
"What a pretty house!" he said instead.
Akaza didn't look at him, but his eyes had narrowed.
Douma felt compelled to fill the silence so he continued. "I'm sure His Lordship told you I'd be accompanying you! I wonder why he wanted us both to come? Two Upper Moons seems excessive-"
"Are you questioning His orders?" Akaza hissed.
Woops. Douma waved a hand and laughed. "Oh, I'd never! I just thought it'd be an interesting topic of discussion."
"We're not here to talk."
Douma pouted and looked back down at the house. Some lights inside were still on and it was easy to see movement. There were several shadows. From his position, Douma already counted fourteen. Surely they couldn't all be demon slayers? Did it really take so many to defeat Lower Moon Four? The Lower Moons changed so often that Douma wasn't sure who it was or what their Blood Demon Art was.
Akaza leapt down the hill and darted towards the house.
Douma was left alone. Awkwardly. He felt quite put out at being left behind with no warning. He had no idea why Upper Moons always did that to him! You shouldn't do that to friends…
He scuffed the dirt with his foot and then went to follow Akaza—
Who had suddenly veered to the left of the mansion instead.
Douma stopped to watch what he was doing, curious.
A demon slayer had run out of the mansion gate to intercept Akaza. When they dodged Akaza's first attack, Douma lit up. They had to be a Hashira! Muzan hadn't mentioned that! How exciting! It looked like Douma wouldn't be getting to kill them, but this was sure to put Akaza in a good mood! Hashira deaths were always something to be celebrated, in Douma's opinion, and he'd heard it been implied that Akaza loved fighting Hashira.
Oh! Maybe he could give Akaza Hashira as presents!
Douma wasn't sure how that would work.
He'd figure it out.
For now, he had to focus on his mission. Muzan would be upset if he just stayed on the hill all night. He said kill the slayers so there were others in the mansion.
Douma went for the direct approach. He went up to the door of the gate, observed the symbol etched in it, then knocked.
No one answered.
He hummed and hopped over it, coming face to face with an old woman. She smelled of wisteria.
Douma smiled at her gently. "Hello," he said. "I'm looking for demon slayers, would you be so kind as to point me towards them?"
"Leave, demon," she said, voice firm. Still, she trembled. "This is a place of healing!"
"I know and I'd hate to hurt the innocent people here but in order to avoid that I need to know who is a demon slayer and who isn't. Won't you please tell me?" Of course, this was a lie. There would be no survivors tonight. No human could knowingly encounter an Upper Moon and survive. Douma also didn't doubt Muzan would approve of them destroying a demon slayer safe haven as it would deny them help and resources, weakening them.
Still, this didn't mean he had to let the innocent, nonslayers suffer! He'd kill them before they had time to be scared.
"I refuse."
Or not! Because she was very uncooperative!
"What a shame!" Douma said.
He swiped at her with his fan, but instead of hitting flesh, it hit a yellow blade. Douma beamed.
A demon slayer! This one was a little injured, but still in fighting form. The old woman ran into the mansion.
"Hi, I'm Douma!" he greeted. The slayer's sword hit his fan again. He flipped over Douma's shoulder, landing hard with a grunt.
"How dare you attack a defenseless old woman!" the slayer shouted.
Douma redirected another attack. Another. And another! The slayer was relentless, moving quickly and striking fast. If Douma was a human he would not have a chance to draw breath. As it was, he didn't actually have to move from his spot. He just twisted his arm this way and that to meet the slayer's blade with his fan.
"Thunder Breathing, right?" Douma asked.
The slayer grit his teeth and adjusted the grip on his sword. He wasn't out of breath yet. Douma wondered what rank he was. He never did learn all of them in his past life. Just Kinoe and Hashira. He usually killed everyone before he could ask their ranking.
"I wonder if any breathing styles have been lost," Douma mused out loud. "I mean, humans have no chance of winning against demons in the long run. Some knowledge is bound to be lost with each death of a demon slayer. Imagine whole techniques never appearing again!"
The slayer resumed his assault. Douma didn't bat an eye.
"I guess that's not completely true. Humans make the same mistakes over and over. I'm sure good things happen over and over too! They come back, just a little different! Like rebirth!"
He caught the sword in his hand. He pulled the slayer closer to his face. The slayer winced. Had he not noticed Douma's ranking?
"There's one flaw with Thunder Breathing I noticed. Your attacks are fast! Don't get me wrong, that's good for weaker demons. One slash is all it takes! But when it comes to a stronger demon, an Upper Rank like me, well, that's not really going to work, is it? You go through all your techniques too quickly and with each repeat, I learn to identify what attack you're going to use next! I can dodge the attack or redirect it… It's no problem now!"
He ripped the sword out of the slayer's grip and put some distance between them.
"Not that I needed to do any of those things! You had no chance in hitting me or cutting my neck. I know all of the Thunder Breathing forms. Water too. I still like to play with you slayers though, just incase something new pops up. You wouldn't happen to have any fancy new moves, would you?" He wiggled the sword by the blade. "I'll give this back if you do!" When the slayer didn't respond, Douma sighed. "No? Too bad."
Douma tossed the sword, slashed into the slayer's chest and walked into the mansion, leaving him to bleed out.
He found the old woman leaving one of the rooms and killed her too. She was probably warning the others. Everyone would undoubtedly be in a panic now. Douma wished she hadn't cause them so much stress and pain. Humans could be so cruel.
He pulled her body up by her wrist and nibbled at her neck.
Not bad, actually! She was very healthy in her old age.
He tossed the older woman's body over his shoulder and continued to walk. One hand held her still while the other ripped her leg off so he could continue to eat while he searched the mansion. Most rooms he looked in were empty, but he'd find the occasional woman. He'd have to remember where he left each body so he could eat them.
When he found children in the closet, he dropped the remains of the old woman. He was mostly done anyway.
"Goodness, what are you two doing here!" he said, crossing his arms. One was a girl and one was a boy, both were wearing white gowns – nurse outfits. They must have been assisting in healing the demon slayers. He clicked his tongue disapprovingly. What a shame that demon slayers got them involved.
Douma raised his fan and the girl wrapped her arms around the boy to tuck him out of view from Douma.
"Wait—" she cried.
Douma silenced her with a slash that cut both of their heads off and stepped back so their bodies could tumble out. He stared for a moment, then closed the closet and moved on.
When he came across what had to be the sixth woman and so far no men other than the slayer, Douma realized what was going on. Women and girls of a variety of ages were living here. Douma knew Muzan played favorites! Having Douma come all this way just so Akaza wouldn't have to kill them!
He shook his head fondly.
It was alright, he was happy to assist his friend.
The room with the largest door led to the infirmary.
There were at least a dozen injured demon slayers in the room. Some struggled to stand and others were unconscious. Douma stroked the back of his claws across the closest slayers forehead, brushing his hair out of his face.
"Poor things!" Douma cried.
One injured slayer charged at him.
Douma barely glanced at him as he cut him down. This discouraged any of the other slayers who were struggling to stand. They must all be low ranking.
"My name is Douma! I am the founder of the Eternal Paradise Cult and Upper Rank Six of the Twelve Kizuki!" Douma said, waving his fan and bowing at the demon slayers. "Please! Allow me to end your suffering!"
One slayer near the back struggled to flip over in his bed. Another, huddled next to him, tried to stop him.
"Yuudai, no—" his plea was dissolved by pained coughs.
Douma had spread his Blood Demon Art as soon as he had entered the room.
"You demons are… pathetic!" the demon slayer (Yuudai?) gasped. His fingers were brushing against his sword that lay on the floor. "And… scared! We kill one Lower Moon and your master sends one of… his strongest demons… to finish the job and… attack innocents!"
There was no point in resisting so all the demon slayer could do was bark nonsense at him. Douma already had his Blood Demon Art suck at their blood. He couldn't feel the cold himself, but he could tell by their breathing that the cells in their lungs had frozen over. The ones who were unconscious were already dying.
"You're the one who defeated Lower Rank Four? That's amazing!" Douma said.
"Damn… you!"
Bark, bark, bark. Couldn't even take a compliment!
The slayer's hand couldn't fully wrap around his sword hilt. He couldn't breathe and his entire body shook with each attempt. Blood and saliva were dripping from his mouth from the effort to get up. He fell off the bed with a pained grunt.
Douma made it easier for him by sitting down in front of him and crossing his legs.
"It looks like it was really difficult. But you did it! Ah, that's so cool…" Douma rested the tip of his closed fan on the boy's forehead so he wouldn't fall forward. "You saved so many lives! You'll go to Heaven for sure! You can rest now and join your friends."
With an abrupt thrust, his fan went through the boy's head, killing him instantly.
He took a quick look around at the other bodies of the slayers, all unmoving. His Blood Demon Art had frozen and killed them.
Aaaand that was everyone! Mostly. Probably. Douma would have to go through the rooms again just to be sure. At the moment, he wanted to check on Akaza! He hadn't come into the building yet. Douma hoped he wasn't having trouble with the Hashira; Muzan would be very disappointed.
When he went outside, Douma was amazed.
He had heard from Gyokko that Akaza enjoyed fighting Hashira for a good while before killing them, but this was the first time he'd seen it himself. He seemed to be thrilled. Douma has never seen Akaza look happy in his life. He had the widest smile Douma had ever seen. He was also chatty. Extremely chatty. Douma wished he could get him to talk so much.
Douma wanted to have fun too! Ah, but Akaza wouldn't want him to interrupt him, would he? The Hashira was already pretty heavily injured anyway—
A shadow flickered across the moon.
Douma's instincts screamed.
The back of his hand shot up to knock away the sword that sunk halfway across his neck. It pulled out before he could break the blade.
Douma drew back and hopped onto the roof of the mansion, running his fingers across his blood that had poured from his own neck. He looked at his blood drenched fingers and palm, grinning. He had almost died just then! That meant only one thing!
Two Hashira!
What a lucky night!
