Chapter Text
Notes: I have no idea where this is going. Not sure if I'm gonna continue.
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I. Biological Imperative (pt.1 Primal)
One year ago
Gray sighed, poking at the campfire, and glanced over at the hunched figure sitting at the very edge of the small circle of light. Normally, managing the fire would be Natsu's job, one which he enjoyed greatly. But now... whatever had been wrong with him the last week or so was enough to put him off even flames, apparently.
A damp branch cracked and crackled, sending up a burst of sparks. A low growl came from Natsu's curled up figure, but he didn't even lift his head from where he had pressed it against his folded arms.
"Alright, enough already! What's with you anyway?" Gray demanded. "You're always terrible on missions, but that one was worse than ever. Were you even paying attention?"
"Lay off," Natsu snarled, all without looking up. He sounded angry — but more than that, he sounded tired and frustrated. "It's none of your business."
"It really is," Gray said, trying to sound annoyed, but beginning to worry in turn. "You've been driving everyone crazy all week, and making a mess of all your missions and the town. Gramps even sent me along with you to try to keep you in line."
In that respect, Natsu was just lucky Erza had left on a month-long mission before all this started. But Makarov had been truly desperate to even try using Gray for damage control instead — half the time, the two of them together just made an even bigger mess.
"...Don't need you," Natsu muttered rebelliously. "I'm fine."
"Come on, don't be like that. Everyone's worrued, you know? Even Happy says you've been weird," Gray cajoled.
He had wanted to refuse and leave Natsu to sort out his own issues, but the cat's uncharacteristic avoidance of his partner had been the last straw. This wasn't just Natsu being moody. Something had to be wrong, for real.
Receiving no reply, Gray surreptitiously edged closer. "I'm not going to laugh," he said quietly. "And I won't tell Gramps, or Erza, or anyone, if you don't want me to."
He stopped, noticing the way Natsu had tensed and begun to lean away. The tight grip he had on his knees, pulled up against his chest, seemed to get even tighter, leaving Natsu a small, rigid ball. But Natsu had also finally raised his head, just a little, just enough for his sharp, hooded eyes to regard Gray. He drew a deep, slow breath, his gaze... measuring.
"Why'd you... get close?" Natsu asked, his voice muffled. His tone was hard to read — the usual pretense of annoyance, and underneath perhaps a bit bewildered, but also mixed with something else that Gray couldn't identify.
Gray sighed. "I want to help," he said bluntly. "We're guildmates, it's okay to help each other out sometimes. So just let me help, will you?"
"Help?" Natsu repeated, lifting his head and looking at Gray with an almost feverish intensity.
It wasn't just the bright, glazed look in his eyes. Gray could see now that Natsu — Natsu, who seemed to have never felt heat in his life — was flushed and red with fever.
"Hey, are you alright?" Gray said, losing track of their conversation as real, deep concern flooded through him. He reached out to touch Natsu's shoulder, which nearly burned under his palm.
Natsu made a strange, soft sound at the contact. "You'll help?" he said again, turning toward Gray and beginning to uncurl from his tight little ball.
He reached out in return, his hand landing on Gray's thigh and sliding down to grasp beneath it. It was a strange kind of touch, but Gray had no time to ponder it. Natsu's grip tightened, and he pulled himself closer. They were almost chest to chest, Natsu's heat was licking across his skin, his breath fanning across his cheek—
Natsu kissed him, firm and insistent, as Gray froze in pure shock.
But why? Natsu had never— This wasn't the time for that, Natsu was clearly sick, maybe it was delirium...
It was so hot. Shuddering, Gray squeezed his eyes shut and moaned softly.
...Ah. It clicked.
It was crazy. But it made sense, somehow.
Gray pulled away, firmly holding Natsu back. The focused, almost predatory gaze that followed him made him swallow heavily. Not in fear, and not in excitement, but maybe something between the two. Sometimes dealing with Natsu was like that, like standing on edge of a blade.
But right now, Gray had to keep a cool head. Something told him that any misstep could end terribly for them both.
He swallowed again, casting for the right words. "This is what you need help with?" Gray asked finally, keeping his tone as even and casual as he could.
Natsu's mouth opened, but he didn't seem to have the words either. His shoulders quaked with every shuddering breath. His skin was scorching under Gray's hand. "Gray..." he started to say, but seemed to be all he could manage.
Half-formed scenarios ran through Gray's mind — Was Natsu in pain? Was he still in there, or was he beyond reason? Could they make it back to the guild? Would Polyushka or Makarov know what this was? Could they help? He'd said he wouldn't tell anyone, but did that still apply? Was this really some kind of... draconic mating instinct...?
What was the right choice? Gray had never felt this completely out of his depth.
Natsu was still watching him, tense and on the edge of something, but holding himself back.
The solution Natsu would want... The simplest one, of course.
'Well, it's not like I hadn't thought about it,' Gray admitted to himself. Maybe it was selfish, but he didn't hate the idea. And he didn't think Natsu would either, even in his right mind.
"Yeah," he said, "I'll help."
~.~.~
When someone suddenly grabbed him and dragged him around a corner into a back alley, Gray's first instinct was to freeze them solid. His magic surged under his skin, making the air mist with the sudden temperature drop. But in the last instance, Gray stopped.
The heat cancelling out his own cold, the too warm hand on his arm — this wasn't a stranger.
Letting out a sharp, annoyed breath, he demanded, "What do you think you're doing, lizard brain?"
Natsu didn't have the decency to even look sheepish under Gray's glare. There was a strange hesitation — then he backed away quickly, his eyes darting everywhere except Gray. His hands curled into fists at his sides, but he looked more ready to run than fight.
The corner of Gray's mouth twitched downward. "Lucy said you were acting weird," he noted. "Happy too. So? What is it?"
"It's... you know..." Natsu minced words, still avoiding Gray's gaze. Then, as he seemed to gather his resolve or reach the point of desperation, his head snapped up, his eyes boring into Gray. "You... Just help me again, will you?!"
Gray blinked, momentarily distracted by the furious blush that had spread across Natsu's cheeks. "Help...?" he finally managed. "With what?"
He could see Natsu grinding his teeth in frustration. "With... with... that thing! Like last year!"
"Last..." Gray started to repeat before it sank in, and he cut himself off with an embarrassed cough. It was his turn to flush and look away. "You mean... You didn't go to Gramps or Polyushka like you should have, did you? I told you to tell them."
"Shut up!" It came out as almost a wail. "Quit nagging! I was going to, but..."
But it was embarrassing. Mortifying, even.
Gray sighed. "You should have sucked it up and done it," he said. "Then you might've had some medicine to take now or something, instead of..." He gestured vaguely.
"If you're not going to help, just say so!" Natsu hissed, his cheeks still burning crimson.
"I'll help," Gray said in exasperation. "But just so you know, that not how you proposition someone you actually want to have sex with. If you tried hitting on me like that for real, I'd definitely refuse."
Natsu made a small, choked sound.
~.~.~
They had ended up taking a simple job that would keep them busy for a couple weeks, most of it taken up by traveling to their destination on foot. Or rather, Gray had taken the job for both of them, since Natsu had been unwilling to enter the guild — or even go into the more populated parts of town.
"Is it already that bad?" Gray asked afterwards. "Last year, you were acting off for days before we, uh, handled it. But Lucy didn't notice anything until now..." A worried line began to form between his brows as he considered the possible implications.
Natsu's mouth twisted unhappily. "No, it's not bad. I can ignore it... probably. But it's annoying," he mumbled, staring down at his feet and the gravel path they were taking. "I keep thinking weird stuff."
"So you finally noticed how great Lucy's curves are," Gray said knowingly.
He received a bitter glare. "No. Not like that," Natsu gritted out. "If it was just stuff like that, it'd be just, whatever, not a big deal. But it's..."
Grimacing, he trailed off. He didn't know how to explain it — that he'd always been aware of how pretty Lucy was and that he certainly cared about her a lot, but that, suddenly, all he could only think of the gap in their power and how Lucy smelled strange, like light and something intangible, the way Loke had smelled, making him wrinkle his nose and... draw away, lose interest, reject.
That last year he'd found himself suddenly paying far too much attention to Mira — Mira, of all people! — acknowledging her strength, taking in the dark, heavy scent hidden under her perfume, which made something deep in Natsu's chest turn oddly. That when Laxus had stalked through the guild on his way to the second floor, Natsu's mind had been a trainwreck of more unintelligible instinct than thought, ending in a deadlock that left Natsu paralyzed with confusion and indecision.
The worst was the way some of those thoughts made sense, if he looked at them from an angle. Twisting together with ones that were completely alien... It all left Natsu faintly nauseous and feeling like he didn't fit in his own skin, like the entire world was a ride he couldn't get off of.
By comparison, it was easy with Gray. Maybe Natsu admired his magical prowess more honestly than usual, maybe the idle thoughts of fighting him were focused a little less on victory and more on a certain anticipation of something just as exciting after... But all of that slotted in easily, naturally.
Those thoughts, which had started after that first night by the campfire, hadn't really left even when the strange, growling heat faded away. In the year after, they would sometimes float to the surface as idle musings when Natsu's mind wandered.
They were something even the normal, human Natsu could agree with, without feeling like he was fighting himself. Gray was always Gray, familiar and comfortable...
Gray was watching him with an amused expression, and Natsu realized he'd started to drift closer as they walked along, until their shoulders were almost brushing against each other. Scowling, he tried to correct his course sharply, only to find himself pulled back — flush against Gray's (naturally) bare chest, Gray armor over his shoulders.
He turned to complain about the manhandling and... Any protest Natsu might have made was cut off as Gray kissed him, simple but growing deeper as Natsu instinctively kissed back, parting his lips with a quiet, pleased hum.
It didn't last long, just a few seconds, but Natsu didn't try to pull away afterwards, staying pressed to Gray's side, so close that his senses were completely filled with Gray. "I said it's not that bad," he grumbled contrarily.
"So? Why wait until it gets bad?" Gray asked, raising an eyebrow. His arm slipped down, across Natsu's back to his waist, and he nudged him to start walking again. "I remember, you were miserable last year."
"I can take it," Natsu muttered. "You don't have to..."
"It's not like I mind," Gray pointed out wryly. "Even if you're not burning up and going crazy. It's... you know, not bad. For me, at least."
Messy and a bit in the rough side, since neither of them had been quite sure what they were doing and both of them kept getting carried away, but still enjoyable.
"Yeah, it’s... nice," Natsu admitted, cursing the blush he could feel on his cheeks, before something else caught his attention. "Wait, going crazy? What's that supposed to mean?"
"What do you think it means, flame for brains?" Gray shot back, rolling his eyes.
Natsu elbowed him sharply, but Gray managed to pull him into a headlock in retaliation. Soon, they were caught up in a full scuffle, cursing and stumbling across the road, to the edge. Another moment and, with a startled yelp, they overbalanced, tripping and rolling down the grassy slope.
Triumphant, Natsu ended up on top when they finally came to a stop. He felt it again — that anticipation, of something just as exciting on the other edge of their tussle, that had sometimes snuck up on him and led to more than one last second turnabout while he was distracted.
But this time, he didn't need to hold it back.
Leaning down, Natsu pressed his lips to Gray's. He could feel him smile into the kiss, arms reaching up around Natsu's neck.
Yes, something just as exciting...
It was embarrassing and awkward and strange, but Natsu thought he wouldn't mind two weeks of heat, if Gray was willing to help him. If it was Gray...
~.~.~