Succumania

"Huff… Huff…" Wisps of steam curled into the crisp evening air. A young girl sprinted forward, her breath steady despite the chill. Her twin pigtails bounced in rhythm with each step, her expression neutral, almost bored.

But inside her head, thoughts were spinning. 

Without thinking, she took a narrow path ahead devoid of people. She would find a snack later, after having finished her jog.

The plan was going smoothly, she successfully infiltrated her target's house and managed to gain a little bit of trust. Though of course, he was still wary of her considering he saw her almost eating someone.

Now all she had to do was observe him and find out if he truly could be salvaged. It wasn't to eat him later, or to make him succumb to her or any kind of tricks succubi had usually up their sleeves, no. It was because they were called here for a reason.

A storm was brewing. Or at least it was what that Nightmare said, Est to Mayu and four other girls before sending them to this world. The end of pleasure was near, and with it, the end of dreams.

Senpai—or rather Luka—was key to stopping it. For some reason, this world was the theater of a multiversal crisis not long ago. During it, something despicable was born, something dangerous enough to create something impossible: an alliance between some succubi and Nightmares.

Mayu was one of them. Alongside four other succubi she had known from a particular school, they had been chosen to step into this world and uncover the truth. Her goal in particular was clear: she had to find a certain detective named Luka and observe him for a while. 

Why? She didn't know. All she knew was that he was important and that gaining his trust was even more so.

That was why she put effort into being nice to him, in her own way.

Though, to her surprise, it wasn't as difficult as she had expected. Initially, she had thought Ayumu would have been better suited for the task, with her cheerful personality and effortless ability to blend in with people. Mayu, on the other hand, was dry, blunt, and sometimes a little mean-spirited.

Then again, in the end, both of them were maneaters—masters of deception.

Yet, strangely, deception wasn't even necessary. Luka accepted her presence far too easily. Even after witnessing her nature firsthand, he treated her as if she were just another girl from the neighborhood.

What an idiot.

If it weren't for his absurd ability to resist them, he would have been dead already.

Or… was that exactly why he acted this way? Did he take comfort in knowing they couldn't truly harm him? Was he simply exploiting that fact?

Mayu slowed her pace as she turned another corner, her thoughts swirling. It was an unsettling possibility, one that made her uneasy.

If Luka was taking advantage of his resistance, it meant he wasn't as naive as he appeared. Perhaps he had more control over this situation than she initially thought. If he knew the truth behind her kind, and was still acting like this… it was dangerous. He could be manipulating her as much as she was trying to manipulate him.

Or… maybe it was simpler. Maybe he was just that rare breed: genuinely kind, nothing more.

She came to a stop, her feet planted firmly on the ground. A man was walking right in front of her, his eyes glued to his smartphone. 

He smelled basic but this would do. She needed to recharge after that little jog.

A flick of her gaze, a honeyed word, and he was hers. She lured him into the shadows, her mind elsewhere as he pressed against her, clumsy and eager. The man's breath was hot and ragged against her neck, his hands fumbling in the dark. Mayu let him carry on, her body responding on instinct while her mind drifted.

She tilted her head back against the rough wall, staring into the dimness. The other girl's faces flickered in her thoughts. What was Ayumu doing? She was tasked with gathering intel on him while the other three were busy dealing with the threat or preparing for the fated day. 

The man groaned, oblivious to her disinterest, and she sighed inwardly. Time to wrap this up. With a subtle shift, she tightened her grip, her legs locking around his waist. His movements stuttered, then stilled, his eyes glazing over as she siphoned his cock of its semen and vitality. Not enough to kill—just enough to leave him dazed, stumbling back into the night with a vague memory of a good time.

She let the man crumple to the floor and adjusted her jacket, brushing off the encounter just like that. 

"If it isn't Mayu." A voice, warm and lilting, spun her around. Its owner stood at the alley's mouth, brown eyes glinting with a familiar spark, a soft smile curving her lips.

"Ayumu?" Mayu stepped past the crumpled man, brows lifting. "What are you doing here?"

"I'm wondering the same thing. Running as always?" the girl asked with a bright smile. Her light brown hair caught the faint light, a stark contrast to Mayu's darker locks. She wore a high school uniform—brown blouse, red-and-black plaid skirt skimming above her knees.

Mayu crossed her arms, eyeing Ayumu with a mix of irritation and curiosity. "Shouldn't you be sniffing around Sen—Luka's past? Or did you get bored already?"

"Oh, I've been busy. He's trickier to crack than he looks—keeps his tracks covered like he knows someone's watching." She tilted her head, studying Mayu. "But you… feeding in alleys? That's sloppy, even for you."

"You tell me…" Mayu sighed, glancing at the dazed man sprawled behind her. "I can't even finish them off." She turned back to Ayumu. "So? What'd you find?"

"Oh, plenty," Ayumu chirped, a hand drifting to her cheek, her eyes glazing with a dreamy gleam. "Did you know he had a friend before? I got loads from him—slipped into his life by posing as his wife."

"Oh, right," Mayu sighed again. "You can shapeshift a bit."

Ayumu giggled again, twirling a strand of her hair as if recounting a schoolyard prank. "It was almost too easy. Poor guy didn't even blink—thought I'd been his 'darling' all along. Luka's name came up a lot, though. Seem they were close once, before he thought he died."

Mayu's eyes narrowed. "So he doesn't know Sen—I mean Luka is alive?"

Ayumu shrugged, her cheer fading just a touch. "No clue why. Anyway, I promised him some fun tonight." She sighed, a wistful edge to her voice. "Can't wait…"

Something clutched at Mayu's chest.

A strange tightness gripped Mayu's chest, faint but sharp.

"Good," she said, nodding, her hands sliding behind her back to clasp together. "As long as you're getting info on him. I hear the preparations are coming along too. Can't wait for it all to go down."

Ayumu's dreamy haze lingered a moment longer before she blinked, refocusing on Mayu. "Oh, right—the plan. The others are moving fast. I can't wait either."

Mayu smirked, though the odd pang in her chest hadn't fully faded. "I can't wait too. This will be fun." she then waved her hand at Ayumu and turned around. "Anyway, I gotta go now. If I don't come home for dinner that might raise suspicions. Have a good night with your 'husband'."

"Thank you!" Ayumu waved her hand back with a smile.

Mayu's shoes crunched against the dirt as she retraced her path, the alley's shadows stretching long and thin behind her. Ayumu's words churned in her head—Luka's friend.

A frown creased her brow. Was Ayumu planning to eat him? That glassy, far-off look in her eyes—it was the same one she'd worn with every victim back at school, a predator savoring the hunt.

Her pace quickened, then faltered, her shoes skidding to a stop. Her muscles coiled tight, breath catching. Was she… worried? For a human?

The thought hit her like a slap, sharp and disorienting. Mayu stood frozen, the chill of the evening seeping into her bones. Worried? Her? She'd drained men dry without a flicker of remorse, watched their lives fade with the same indifference she'd just shown that alley fool. And yet here she was, chest tight over some stranger tied to Luka—a human she was supposed to be sizing up, not protecting.

She shook her head, pigtails swaying, and forced a scoff. "Ridiculous," she muttered, shoving her hands into her pockets. It wasn't worry—it couldn't be. Just strategy. If Ayumu went too far, it'd destroy Luka's trust in them.

Her legs moved again, slower now, carrying her toward Luka's house. Ayumu's giggle echoed in her memory, too carefree, too hungry. Mayu's jaw tightened. She'd have to keep an eye on her—make sure she didn't blow this.

By the time she reached Luka's doorstep, the unease had settled into a low simmer. She rapped on the door, schooling her face into its usual mask—bored, a touch playful. It creaked open, and there he was, hair tousled and damp, like he'd just stepped out of the shower.

"Oh, Mayu's back," he said with a warm greeting smile. "Did you run well?"

"Eh, of course," she smirked, slipping past him. "So, what's for dinner, Senpai?" she added the last word with a teasing tilt.

"Eva came by with some odd stuff, so… soup it is. Made some garlic bread too, after my lessons with Vinum." His tone was casual, as he shut the door behind her.

Mayu arched a brow, trailing him into the kitchen. The air carried a faint tang of herbs and toasted garlic, warm against the lingering chill she'd brought in. Luka moved with a practiced ease, stirring a pot on the stove, his damp hair catching the light. Too relaxed, she thought. Too normal. It grated on her nerves.

As usual, she was getting no reaction from him.

"Lessons with Vinum?" she probed, leaning against the counter, arms crossed. "What's that about?"

"Just some general course about Succubi. I need to gather as much info to protect myself from you all," he added, shooting her a smirk.

Mayu's lips twitched, a flicker of irritation crossing her features. "Protect yourself? From little old me?" she drawled, her voice dripping with mock innocence. "How hurtful, Senpai. And here I thought we were getting along so well."

Luka chuckled, setting the spoon down and turning to face her fully. "Oh, we are. But you can't blame for being cautious when you almost killed a guy, right?"

Mayu's smirk faltered for a fraction of a second before she recovered, her expression shifting into one of playful defiance. "Not my fault if he wanted it," she teased. "That's why I call you all turtles. Slow thinkers, all of you," she waved her hand haughtily.

"Hm," Luka nodded, pouring the soup in bowls. "Anyway, go take a shower. You smell sweaty and musky. Took a snack on the way home?" 

"Whoa… Senpai, you can even tell that?" she let out a low chuckle. "Don't tell me… You were spying on me?"

"Nope," Luka shook his head with a sigh. "Now stop playing around and go change. I will set the table for everyone."

"'Kay~" Mayu sing-songed, her tone light but her mind already racing. She turned on her heel and headed for the bathroom, her smirk fading as soon as she was out of sight. 

That same tightening in her chest wasn't going away. 

As she stepped into the shower, the hot water cascading over her, Mayu let out a frustrated sigh. This mission was supposed to be simple: observe Luka, gain his trust, and figure out why he was so important. But nothing about him was simple. No, he was just…

"I don't know how to kill a dream-type succubus but I might find out if you fuck with the lives of the people here."

Those words echoed in her mind. Why was she feeling so threatened by this? Was it why this pain in her chest wasn't going away?

And then there was Ayumu. Mayu's jaw tightened as she thought of her fellow succubus. If Ayumu truly killed her Senpai's friend, it could ruin everything. 

Shit, I'm scared… she gritted her teeth. Why? Why was she scared so much of this guy? It made no logical sense at all, he did nothing worthy of that fear.

What Succubus-chan said the other day… Was it true? 

Mayu had never felt that feeling of protection Succubus-chan had described. And yet, she couldn't bring herself to treat Luka as just a mere snack or future conquest. There was something about him—something that made her hesitate, something that made her chest tighten in a way she couldn't explain.

As she walked back into the kitchen, the aroma of soup and garlic bread filled the air. Luka was setting the table, too many bowls for a normal house, but considering the number of "guests" he was hosting, it was expected. He glanced up as she entered, offering her a small smile.

"Feel better?" he asked.

"Much," she replied with a sigh, her arms crossed behind her back. She took a seat at the table, her gaze avoiding him. The tension in her chest was still there, a dull ache she couldn't shake. She hated it—hated how he made her feel so off-balance, so… human.

There was no one in the living room for now, the other succubi all resting in their own room. Luka sat down across from her, his eyes flicking to his phone quickly before going back to hers. He blinked multiple times before smirking. "Something's on your mind?"

Mayu's lips curled into a smirk, though it lacked its usual edge. "Just thinking about how boring you are, Senpai."

"That's… the second time someone called me boring today," he sighed, reminded of Succubus-chan's earlier remark. 

"Well because you are," she remarked. She then picked up her spoon, stirring the soup absently. "Anyway, I'm too hungry to talk."

For a moment, they ate in silence, the only sound the clink of spoons against bowls. Mayu's mind, however, was anything but quiet. She kept replaying Luka's words, his gentle attitude, his calm exterior and his ability to be immune to succubi…

When finally, she broke the silence. "Hey, Senpai."

"Hm?"

"What would you do if… one of us went too far? If we hurt someone you cared about?"

Luka paused, his spoon halfway to his mouth. He set it down slowly, his expression thoughtful. For a moment, he said nothing, his gaze steady as he looked at her. Then, with a calm that sent a shiver down her spine, he replied, "I would kill you, simple."

Mayu's smirk faltered, her spoon freezing mid-stir. She stared at him, her brown eyes narrowing slightly as she searched his face for any hint of jest. But there was none. His expression was calm, almost serene, but his words left no room for doubt.

"Kill me, huh?" she chuckled. "You think you could?"

Luka leaned back in his chair, his arms crossed, his gaze never leaving hers. "I don't know how to kill a dream-type succubus," he admitted, his tone matter-of-fact. "But if you hurt someone I care about, I'd figure a way. I already have plenty of ideas."

Mayu's lips twitched, her smirk returning, though it felt more forced than before. "Damn Senpai, scary~"

"Why did you ask this question?" he asked back, his eyes darkening.

Mayu's chest tightened, that same unfamiliar ache returning with a vengeance. Shit, she thought. Why did she ask that? Why had she given him even the slightest hint that something was wrong?

She stared at him, the soup forgotten, her mind racing. That wasn't a bluff. He meant it—every word. And it terrified her, not because she doubted he could try, but because she believed he would . Her fingers tightened around her spoon, the metal cool against her palm. Why did that scare her so much? He was just a human—immune or not, he shouldn't have this hold over her.

"Just curious," she said, her tone flippant, though her fingers tightened around the spoon.

Luka's gaze didn't waver. "You're hiding something, Naoe Mayu."

She froze. Her spoon clinked against the bowl as her hand stilled, her smirk slipping entirely. For a moment, she couldn't breathe, couldn't think.

"Hiding something?" she repeated, her voice steady but her mind racing. "What makes you say that, Senpai?"

Luka leaned forward slightly, his elbows resting on the table, his gaze piercing. "Don't fuck with me Mayu. What is going on?"

Mayu's jaw tightened, her fingers curling around the edge of the table. She wanted to laugh, to brush it off, to tell him he was imagining things. But the words caught in her throat. Because he was right. She was hiding something.

And she wanted to tell him.

"You're overthinking it," she said at last, her tone dismissive but her eyes avoiding his. "I'm just… bored. That's all."

Luka didn't move, didn't blink. His silence was louder than any retort, a pressure that pressed against her ribs. "Bored," he repeated, the word flat, unconvinced. He tilted his head slightly, studying her like a puzzle he was piecing together. "You're a shitty liar when you're rattled."

Mayu's eyes snapped back to his, a spark of defiance flaring. "And you're a shitty detective if that's your best guess," she shot back, her smirk creeping back, brittle but sharp. "What, you think I'm plotting something juicy? Hate to disappoint, Senpai—I'm not that interesting."

He didn't bite. "You asked about hurting people I care about. That's not idle chit-chat. Something's eating at you, so spill it. Or I'll figure it out myself."

She stayed silent, her head low and her eyes avoiding his. 

Finally, Luka sighed, breaking the tension. "Fine," he said, his tone softer now, almost gentle. "You have nothing to say but it's clear something is eating at you. I don't want you to think that when something is wrong, you can't ask me for help, that's all."

Mayu's fingers clenched around the edge of the table, her knuckles whitening as she stared at the half-empty bowl of soup. The silence became unbearable until she couldn't take it anymore. Her head snapped up, her eyes tearing up from fear and frustration.

"Shut up," she finally hissed, her voice low and trembling.s

Luka blinked, caught off guard. "What?"

"Don't—" She cut herself off, her jaw tightening as she glared at him. "Don't give me that 'I'm kind' bullshit. Don't act like you care. You don't know what's going on, so just… stop."

"Then tell me. What's going on, Mayu?"

She hesitated, her chest rising and falling with shallow breaths. For a moment, it looked like she might bolt, but then the words spilled out with a devilish grin. "A friend of mine is going to eat your friend tonight. She's posing as his wife. And you—" She stopped herself, a cocky grin on her face. "And you won't be able to do anything about it."

"Is that so?" Luka replied in a chilling tone, his eyes narrowing. 

"Yeah, sorry about that, Senpai—"

His fist slammed into her face, the impact a thunderclap. The table flipped, bowls of soup arcing through the air as Mayu hurtled backward. She crashed through the bay window in a spray of shattered glass.

Nearby doors opened as the other succubi were alerted by the sound.

"Hey! What the hell is going on!?" Morrigan shouted, her blue aura itching to throw down.

Mayu landed hard in the garden, skidding across the dirt. She staggered to her feet, hand brushing her cheek where a trickle of blood seeped from her lip. Her eyes flicked up, meeting Luka's through the broken window.

"Keep an eye on her," he barked, pointing at Morrigan as he strode toward the door. "I've got to go."

Mayu spat a crimson glob onto the grass, wiping her mouth with the back of her hand. The sting in her cheek pulsed, but it was nothing compared to the fire roaring in her chest—anger, shame, and something she couldn't name.

"Wait, Senpai…" she coughed, trying to rise, but Morrigan stepped forward, blocking her path.

The blue-haired succubus's eyes locked on Mayu with suspicion and irritation. "You've got some explaining to do," she growled, cracking her knuckles. "What'd you say to set him off like that?"

Mayu chuckled, low and bitter, brushing dirt off her jacket. "Just told him the truth. Guess he didn't like it." Her gaze darted past Morrigan to the house, where the other succubi—Vinum and Eva—emerged, their expressions a blend of confusion and wariness.

"The boy doesn't punch through windows over nothing," Vinum said, her voice cool, arms crossed as she assessed Mayu. "What truth?"

She dropped her head down under the glare of the others. "A succubus got her claws in his friend. Dinner plans, you know? Thought he should know."

"I don't get it…" Eva muttered. "Your friend is inviting Luka's friend to dinner?"

"No, you idiot," Astaroth's hand slapped the back of Eva's head. "Luka's friend is the dinner."

"Oh…" Eva nodded, catching on.

"You stay put," Lilith declared, stepping outside with a stride that radiated menace. Her icy eyes locked onto Mayu, unyielding. "Move, and I'll tear your head clean off your shoulders."

Mayu's bravado faltered, but she didn't budge, her gaze flicking to the living room where Luka had disappeared. 

"If you let me go, I swear I can help," she said back.

"Let you go?" Lilith's tone was skeptical, cold. "Why?"

"That succubus—she's an acquaintance," Mayu explained, her words quick, desperate. "I might be able to talk her out of it."

"That's something to tell Luka, not me," Lilith replied, unflinching. "And he's already gone."

"I swear I'm not his enemy," Mayu insisted, her voice cracking slightly.

"It's pointless now," Vinum sighed, her gaze distant, almost bored. "We just have to hope his friend is still breathing."

"Vinum," Astaroth turned to the smaller succubus, her tone shifting to unease. "Do you think Luka'll be okay? If his friend's dead…"

"I'm more worried about that acquaintance of hers," Vinum said, her eyes sliding to Mayu with a chilling calm. "Luka is known to have quite the genocidal streak against succubi."

The room fell into a stunned, suffocating silence, every gaze snapping to Vinum.

The night had already just begun.