Demonslayer Short Stories

Siren Song (Nakime x Reader Fluff)

Miyumi was a siren roaming the seas around Japan, luring in human sailors to trap and eat. She had no idea about what happened above the water, so she didn't know demons existed. Miyumi lived alone, being the only siren who lived on the east side of Japan.

One day, she'd been playing in the waves when she heard a faint melody. The tune sounded like it came from a string instrument, and was quick and slightly eerie. Miyumi, although she was the siren, couldn't help but stop and listen. With two quick swishes of her long, green tail, Miyumi swam atop a rock near the shore. She strained her eyes, but couldn't see the player.

Who's playing that? For how loud it is, I can't imagine they're far. The beach was dark and empty, save for one small wooden building. Overtaken by curiosity, Miyumi shifted to her human form, tail disappearing amongst folds of emerald green fabric. A raven black color bled into her waist-length white hair. The only flaw in her form–in all sirens' human forms–were her eyes. They were never a natural human shade of eye color, always a dark color from the ocean. Miyumi could only hope no one noticed them. She crept closer to the door, stumbling a bit on her new legs. As she entered the building, the doorway disappeared behind her and a scene of chaos unfolded before her.

Buildings, stairs, and doors appeared everywhere, facing every which way, even upside down and sideways. The song grew louder, coming from the left. Miyumi looked around in awe. Were all human houses like this?

The song shifted into something slower but equally, if not more, eerie. The melody tugged at Miyumi's ears, and she involuntarily opened her mouth. Ironic, I though I was the siren. She started to hum in harmony with the tune. The tune faltered slightly, before resuming. Miyumi started to sing, using her siren voice. She started to follow the melody, breaking into a run.

The song quickened its pace, as if testing her, and a more resonant note came from the biwa. The next thing Miyumi knew, she was falling through the air, landing on an elevated wooden platform. She struggled getting up, disgruntled and still wobbly on her legs. As she looked up, she saw a woman kneeling at the back of the platform.

The woman had long, straight, black hair that reached to the ground and covered her face. She wore a black kimono so that the only pieces of grayish skin showing was her forearms and her face from her nose to the hollow of her neck. In her lap was a biwa, presumably the one playing the tune.

"Hello?" Miyumi said tentatively. "Were you the one playing the song?"

"Yes." The woman replied curtly, not sparing Miyumi a glance. "How did you hear me?"

"There was a house on the beach." Miyumi looked around, still in shock. "What is this place?"

"The Infinity Castle." There was a hint of pride in the woman's voice. "Death trap for humans, shelter for demons."

"Demons?" Miyumi stepped back. "What's a demon?"

"A creature who eats humans." She hummed to herself. "Like a siren, but we can't go into the sun."

Miyumi tensed, ready to run. "Sirens?" She asked warily. "Wait.. we?"

"I'm a demon." She parted her hair to reveal one large, pink eye surrounded by veins. "Didn't you notice by my skin color, siren?"

Miyumi's eyes grew wide. "I- How did you-"

"Only a siren can have a voice like that." The woman interrupted. "And no human's eyes are that shade of red."

Crap, she noticed. "Well- um.. I'm.. gonna go now.." Miyumi turned to try and spot the exit, but the only things in sight were buildings, stairs, and more buildings.

"You can't leave unless I make an opening." A slight smile graced the demon's features, and Miyumi noticed just how pretty she was. "What's your name, siren?"

"Miyumi.." Miyumi replied, a little unsettled by the way her tone shifted. "What's yours?"

"Nakime." The demon said. "Please stay. I don't like-" She stopped, a strange expression flitting across her face before she hid her face again. "I would hide if I were you." Leaving almost no time for Miyumi to react, she plucked her biwa again, bringing a tall, pale man wearing a formal looking suit and hat to a platform below. As his red eyes turned to study them, Miyumi felt a shiver go down her spine. She could tell this man was powerful.

"Nakime.." The man hissed. "Who is this and why is she here?"

"This is Miyumi, Muzan-sama." Nakime spoke with an even voice, but with a slight undertone of fear and guilt. "She heard me playing my biwa, and found the entrance to the Infinity Castle."

"And you like her." The man–Muzan–clarified, his tone unreadable.

"Yes." Nakime seemed to have lost all and any emotion she'd regained from speaking with Miyumi.

Muzan sighed. "Because you've served me well, you may keep her. Don't let her interfere with your work."

"Yes Muzan-sama." Nakime hid her relief well, but Miyumi still caught onto it.

"That is all." The man snapped his fingers.

"Yes, Muzan-sama." Nakime strung her biwa again, and Muzan blinked away.

A silence fell over the castle once he left. Miyumi decided to break it. "What was that?"

"That was the king of demons." The raven-haired demon sighed. "You're lucky he let you live."

"The king-" Miyumi recoiled slightly. "The king of demons?"

"He has control over all demons." Her tone suggested that she wanted the topic to be dropped.

"Eh- alright, but um.. What was that part about keeping me?"

"Will you stay here? It gets.. lonely."

For whatever reason, Miyumi wanted to say yes, wanted to stay with this demon whom she'd just met. But..

"I'm sorry, but I can't live out of the ocean for long. I wish I could stay, but I get dehydrated too easily."

Nakime sighed. "I expected as much." She plucked her biwa, opening an exit to the beach.

"I'll visit." Miyumi smiled over her shoulder as she stepped out of the doorway. "Promise." The opening disappeared as soon an Miyumi stepped out, and she looked back wistfully as she dove into the sea again and shifted. She smiled as she heard a biwa's melody, the melody that had captured the heart of a siren.