Chapter Text
Ever since that night, Lucy had started noticing something very, very odd. It wasn’t just one big thing; it was tiny bits and pieces here and there—something she wasn’t even sure anyone else would notice unless they've known him for years. Yes, she was sure of it: something was definitely up with Natsu.
After years of lecturing him about constantly trespassing, that night, she finally gave up entirely and made one crucial mistake: allowing him to “stay as long as he needed.”
Originally, she had meant just that night—maybe even until the next morning. But Natsu had interpreted it in his own way: that he could now come and go whenever and for however long he pleased.
Maybe it was the sadness in his eyes when he first admitted his sleeping problem or the quiet happiness he carried each time he entered through that window, but she didn’t fight him on it, either.
Since then, she came home more often to Natsu and Happy snoring loudly in her bed than to an empty house. Lucy was fine with this. Or at least, that’s what she told herself—except for a few things. First, Natsu had started hoarding things in her apartment. In the beginning, it was normal stuff: Blankets, pillows. She didn’t mind initially, but he kept bringing more and more. It was as if he had an endless supply. By the time he stopped, there were so many on the bed she feared he would get lost in them. What a fire dragon needed all that warmth for, she had no idea.
Then came the trinkets and mementos he picked up on jobs. This didn’t bother her as much; in fact, she found it almost cute. Especially how he remembered every tiny little detail about them, no matter how old they were.
The strangest thing, however, had been his skinship. Or rather, the drastic increase of it.
Natsu never cared much for personal space, but lately, he’d been almost… clingy?
It started with small, lingering touches here and there, barely noticeable. A hand on her shoulder that stayed for half a second longer than usual, or fingers softly brushing hair from her face when she was hurt or sad.
Over time, the touches grew bolder. An arm constantly around her shoulders, his body always close, never stepping too far away.
Is he even aware? She wondered. Does he know what he’s doing?
Or maybe she was overthinking. Perhaps this was just normal for best friends, or maybe they were just normal for Natsu.
Lucy sighed and stood up from her chair. With so much on her mind, she could hardly focus on her writing.
Maybe I just need some fresh air. Slipping on her jacket and shoes, she left the apartment and headed to the guild. Rent was due soon, and she’d been thinking about taking a new job anyway.
As she walked, a familiar face bounded toward her. “Yo, Lucy!” Natsu beamed. “What’re you doing out?”
“I was looking for you, actually. I was hoping we could go on a job together.”
“Aw, really? I kinda wanted to hang out at your place today,” he said, sounding dejected.
“ The Natsu Dragneel wants to stay home instead of going on a job?” Lucy snickered. “That’s so unlike you.”
“I dunno… I just haven’t felt very adventurous lately.”
“Aw. Well I’m a bit low on funds and kinda hungry…”
“Easy! I’ll buy food today!” He offered cheerfully.
“Are you sure? That’s not like you either. Usually, I’m the one buying.”
“Yeah! If it means we can stay home today, why not?” His arm easily draped over her shoulders, guiding her back toward her apartment.
Walking side by side, Lucy felt oddly nervous. Was it okay to feel happy about this? She looked up at him. He was facing forward, smiling like this was the most normal thing in the world. She couldn’t tell what he was thinking in the slightest. Was it okay to think that there might be something more?
After ordering takeout and eating their fill, Natsu threw himself onto Lucy’s bed.
“Ahh Beddy I missed you so much! I could lay here all day!” he exclaimed.
Lucy cleaned up and sat beside him. “Never took you for somebody who likes lounging around all day.”
“I’m not! But lately, it’s all I wanna do.”
Lucy thought for a moment, then prodded, “What about your house? Why here?”
Natsu had his face pressed into the blankets—something she’d seen him often since he started staying over. His eyes began to droop, and his muffled voice answered quietly, “My house doesn’t smell like you.”
Lucy’s cheeks flushed. “Wh-what?”
Suddenly, Natsu’s eyes flew open. He sat up, his hand covering his mouth, looking anywhere but her. His face burned a deep red. “Uh, I mean–” he stammered.
Whoa. “Natsu? Are you okay?” She leaned closer.
“I, uh–” He inched away, something he’d never done before. His breathing quickened, and there was a strange look in his eyes—something she did not recognize.
“Are you sure you’re not sick?” she asked, reaching for his forehead again.
Before she could touch him, Natsu grabbed her hand. “I have to go,” he blurted out, leaping up and rushing for the door. But Lucy was faster, and in a flash, she blocked his path.
“Lucy, let me go.” he said, his voice strained.
“No. I’m worried about you, Natsu. Tell me what’s been going on, and I’ll let you leave.”
“ Please , not right now.” His eyes trailed down her body, and he clenched his fists. Any more of this and he feared he might lose control.
“Just for a little bit. Tell me what’s wrong,” she pleaded, her voice softening.
To her surprise, Natsu grabbed her waist and pulled her close, resting his head on her shoulder.
“Please don’t be mad.” He whispered, his voice was shaky.
Lucy gently wrapped her arms around his neck, her fingers threading into his hair. “I could never be mad at you. Not truly.”
“Lucy, I… I need to mate you. I need to touch you, need to bite you. Please… let me mate you.” His voice came through choked sobs, thick with need.
Her face flushed. Of all the things she thought he might say, she didn’t expect this. Without a word, she backed up, pulling him along with her until they fell onto the bed.
She hid her mouth behind her hand and looked up at him through her lashes. “I don’t mind… If that’s what you need.”
“If… If I hurt you… promise you’ll stop me.”
“You won’t hurt me. I trust you.”
“Promise me,” he growled.
“I promise.” Before she had time to think, Natsu dove in, his lips crashing with hers. His kisses were rough and alight with desire. His sharp teeth nibbled on her lip and she gasped, his tongue forcing its way into her open lips. He explored her mouth ruthlessly, running over her teeth and interlocking with her tongue.
“Taste so good,” he broke the kiss and immediately moved to her neck, biting and sucking bruises into any piece of skin his lips could reach.
“Lucy. Smell so good. Lucy, Lucy, ” He spoke her name like a mantra, repeating it over and over. His hands flew under her shirt, touching and grabbing everything they came across, as if trying to memorize her very shape through his fingertips.
Lucy gasped and moaned, the ferocity in his actions fueling the fire in the pit of her stomach.
Suddenly, she heard a loud rip! and looked down to see her shirt and bra falling to pieces beside her. What surprised her even more was the fact that Natsu’s hand had morphed, and she could see scales slowly crawling up his skin, and sharp claws where his fingernails should be.
“Natsu!” she yelped.
“Sorry,” he breathed, his voice shakier than ever before. “Can’t… help it…”
His hands quickly moved to grasp her breasts, pinching and pulling her nipples with his fingers. “So pretty, Lucy. So beautiful.”
Lucy’s face burned deeper at his praises, and she moved her hand to her face again, trying to shield herself in shyness.
“Don’t. Let me see you. Let me hear you, Luce. I need you .” And before she could speak, he pulled her right nipple into his mouth, rolling his tongue around it. She threw her head back and moaned. All of these sensations were new for her, and she wasn’t prepared for just how good it all felt. On top of all that, everything Natsu did was so intense, every place he touched lighting her skin aflame in his wake.
His mouth popped off of her chest with a loud pop! and he trailed kisses lower and lower down her body, until his teeth reached the hem of her skirt. His scaled arm came up to remove it, but–
“Wait!”
Natsu stopped in his tracks. He looked to her, his pupils dilated and breathing ragged, barely holding his composure. And yet, he dare not move a muscle.
“Um… Let me do it. I like this skirt, y’know?” She slid the fabric down, nervously, having never before done this in front of another person. Sure, Natsu had already seen it all, and she found a small bit of comfort in that. But it had never been like this before, not in this context.
As soon as her skirt and underwear were gone, Natsu pulled open her legs, nibbling on the soft skin of her inner thigh. “Smell so good, Lucy.” he repeated. Lucy struggled to keep herself from closing her legs in embarrassment. Not that she’d be able to with him holding her in place, anyway.
“Need to taste you.” Natsu’s tongue rolled between her folds, eliciting a sharp gasp from her as it brushed over her sweet spot. He circled his tongue around her clit before sucking it into his mouth and hollowing his cheeks.
Another moan escaped Lucy’s lips, and her hands dug into his hair, gripping on for dear life. A deep, slow rumble emanated from Natsu’s throat, seemingly pleased by this. It all felt so good , and yet, somehow, it wasn’t enough.
“Ngh, Natsu! Fingers… put your fingers in.” She struggled to speak. Natsu obliged, his finger finding its way between her walls, sliding in until it reached his knuckle. He slid it in and out, slowly, in stark contrast to the feral ministrations from his tongue. Soon after, his middle finger slid in along with it, and Lucy keened at the pleasant stretch, his fingers much wider than her own.
“Mmh, I’m getting close…!” she managed out as her pants and moans became more frequent.
But before she could finish, he removed his mouth and fingers. “Sorry, Luce… just hang on a bit longer for me…”
He stood up to remove his pants, and Lucy’s breath caught in her throat as his length swung free. It wasn’t entirely human. She could see soft scales at the base, fading into regular skin as it reached the middle. And, for some reason, it almost seemed like it was slightly swollen at the base. Was it just her imagination?
Lucy decided to just ask. “Does it… um, look like this all the time?”
“N-no. Only recently… Usually it’s more normal.”
Lucy gulped. She wasn’t sure if she was relieved or disappointed.
Natsu lined himself up, guiding his head through her folds until it caught on her entrance. The tip slowly slid in, and his head dropped to the mattress beside her. He bit onto the blanket, every ounce of composure left in his body focused solely on entering slowly, determined to not hurt her.
Lucy’s hands reached the nape of his neck again. “It’s okay,” she cooed. “You’re not going to hurt me. I can take it.”
“Lucy.” A low growl sounded behind his voice as his mind slipped further, losing itself to his urges.
“Go ahead. I’m stronger than you take me for, stupid.” She chuckled softly.
And that’s all it took. Her soft smile, her quiet laugh; something inside him broke, and he thrusted into her harshly, bottoming out. She had to squeeze her eyes closed, pain and pleasure mixing as he filled her to the brim. But he gave her no time to breathe, his rough thrusts consistent and rushed. “Lucy, Lucy, Lucy…” like a prayer, her name fell from his lips over and over again.
Lucy’s hands tugged on his hair, grabbed at his back, looking for anything she could find to ground herself. Her senses were overwhelmed with him, and it was all she could do to moan as all her pain faded into mind-numbing pleasure.
His pace began to stutter, his movements growing sloppy and she knew he was getting close.
Natsu snarled and snaked his hand down to her heat, his fingers finding her clit and attacking it, working to bring her as close as he was.
“Gonna breed you,” he growled. “Gonna fill you with my pups. Need to.” His words were broken and filled with desire, and she groaned as they fanned the flames in her groin.
“Need… to bite…” he breathed against her neck. She turned her head to reveal her neck in response, a show of submission that made Natsu’s head reel and his mouth water. Without a second thought he bit down, hard, making Lucy scream. He held on as his thrusts quickened, and then he was groaning, spilling his seed into her as he fucked her through his orgasm.
And then she was coming, too, the sensation of his teeth on her skin and the sounds of his moans bringing her to her climax right after him.
“Lucy…” His thrusts slowed to a stop, and he finally released his hold on her neck, languidly lapping up any blood that began to seep out.
They laid there like that for a minute, catching their breaths as they held each other closely. FInally, Natsu broke the silence.
“Sorry…” he whispered against her neck.
“What for?” she chuckled.
“I, uh… I lost control there. And this looks like it’ll leave a mark for a while… Sorry.” Guilt washed over his face. Lucy thought he looked cute, pouting like a sad dog who’d just been caught.
“Don’t feel bad,” she giggled. “Actually, I kinda liked it.” She looked away from him, unable to hide her embarrassment.
His eyes widened. “Really? Well, in that case.” He bent down and kissed small pecks around the mark, before trailing up her jaw to meet her lips in a soft kiss. He looked down at her, admiring his work. “You look beautiful marked by me like this.”
She giggled. “Do I now?”
“You do. When it fades, let me mark you again.”
“Only if you put it in a less conspicuous place.” Lucy laughed.
“Boooo! Boooring. Everyone should be able to see it and know who you belong to.” He turned them over on their sides, snuggling her close.
The mark never did fully fade. A ‘mating mark,’ as they learned from Gajeel and Levy, occurred only during a dragon’s rut and lasts a lifetime, bonding their very souls together. Lucy didn’t mind it; in fact, she sometimes found herself admiring it in the mirror when no one else was around.
Through their research (or rather, Lucy’s), they’d discovered that most of Natsu’s strange behaviors—his constant desire to sleep, the blanket hoarding, the scenting—were all symptoms of his rut. Apparently, a dragon’s rut came once every 3 months after choosing a mate, and lasted until they lay with their partner. Until then, the dragon would shield itself from the outside world, instinctively nesting in its “cave.”