They'd been acting weird for a while now.

And it wasn't just him noticing these things, either. As much as Zoro liked to pretend he was about as observant as an Arabasta cactus, Usopp didn't miss the glances he sent over to the pair whenever they stood a little closer, talked a little longer, smiled a little wider. There was something going on, and he was going to find out what.

It was dinner time, and although you might think that if something was going on between the two they'd either sit right next to each other or as far as they could, everyone sat in their usual seats. Nami was smiling at Sanji as he babbled on and on about "how beautiful she was when she ate the food he prepared especially for her". Luffy was trying to discreetly nab a potato off of Chopper's plate. And all the while Robin merely sat with her usual serene glow beside Zoro, while said swordsman forced as much food as he could down his throat before Luffy moved on to his plate. Usopp had already finished in his normal rush, and was now inspecting the surroundings.

So things seemed pretty normal – Nami humoring Sanji, Luffy stealing food. But at the same time, almost… too normal. Sometimes they'd manage to catch each other's eye, and Luffy would just grin mischievously, like a cat eying a mouse. It was certainly a look Usopp had never seen the Captain give anyone before.

In the past few weeks, they'd been travelling through rougher-than-normal seas, too. Well, normal enough considering it was the Grand Line, but still a little too often for the Straw Hat pirate's tastes – especially considering they carried three devil's fruit users. As usual, it was mainly Zoro, Sanji and Luffy that went to take out the big waves, but one thing had changed, even turned into a pattern.

Luffy always handed his hat to Nami.

Before, sometimes he wouldn't bother to take it off. Other times, it was just whoever was closest. But now it was almost routine for the teen to toss it over to the skilled hands, and for Nami to catch it. The only change that seemed to occur through this consistency was that recently, he'd place it on her head instead, making her grin.

It was some kind of inside joke, almost. Usopp couldn't understand it.

All he knew was that they had grown strangely closer in the past few weeks, and he couldn't help but ask himself why. Curiosity did kill the cat, but satisfaction had brought it back, didn't it? So he pressed on, occasionally lingering outside doors that he knew the two were behind by themselves. These times seemed to have increased in number as of late, too.

Sometimes there would be the soft murmur of hushed voices – that was one Usopp was still struggling to overcome. Since when did Luffy understand the meaning of soft and hushed? Nevertheless, the times that there was a simple silence (an even more bizarre aspect when linking it with their captain) were even more common. Not total silence, that is – sometimes there would be the quiet sounds of movement, and occasionally single words would escape that were too guttural for even him to understand.

They had to be planning something. Maybe a party… for him. How long till his birthday? Seven months? Oh well, it was still a possibility if you factor in how invaluable he was to this crew.

That night, Usopp lay awake in bed thinking it over. What was going on? The trust between them had gone from that of the blind, baseless dependence Luffy placed in all of his nakama to something… more. Something different, something he knew he recognized, but couldn't quite place it. Frankly, it was driving him up the wall.

He was kept up well into the night with these crazy thoughts, used to the soft snores of the other men that slept in the cabin. Sanji and Chopper were fairly quiet, while Zoro and Luffy –

Wait. Zoro was obvious as always, mouth wide open with a spot of drool slowly crawling down the side of his face. But Luffy was uncharacteristically quiet, turned away from Usopp. After a couple more minutes of puzzled silence (on Usopp's part), Luffy turned over and slipped out of bed, pulling the notorious hat on as he went. He was being subtle, careful not to wake anybody.

Hungry, Usopp thought silently, turning over, he's going to raid the fridge. Sanji will be thrilled.

But then why take his hat?

Usopp sat up, realizing this was his chance. Luffy sneaking out in the middle of the night was not uncommon considering his insatiable appetite, but there was a different mood to it. A kind of impish air had surrounded him as he carefully closed the door behind him, mindful of the rest of the men in the room.

After a few moments of brief hesitation, Usopp lifted himself off his hammock, climbing down the side rather than jumping so as not to alert anyone of his presence. He moved to the door, pulling it open and closed without a creek, thankfully. Good old Merry.

He peeked around the side, and his eyes narrowed when his suspicions were confirmed. The kitchen was empty. Whatever reason Luffy had chosen to disturb his beloved sleep cycle, it wasn't to satisfy his one and only even more demanding one.

Did that mean there was a new cycle in Luffy's lifestyle? One that he placed above sleeping and eating? And how did Nami fit into it?

And then it hit him. Usopp felt like an idiot. Of course it was Nami, it had to be Nami – Luffy must've developed some kind of… of…

Love for maps! They were probably in Nami's cabin right now, all over the map-making table – Luffy had to be learning all kinds of new things. Nami was a pro, after all. At map-making. Oh, the maps they must be making now.

Usopp rubbed his chin, leaning against the doorway. But why hide it? That was all that he could think of. For what reason would Luffy feel the need to keep this from them? Map-making was hard – maybe he thought they'd discourage him, telling him things like he'd never be able to do it?

But Nami had to be a pretty good teacher if this had carried on for such a long time. In truth, the sharpshooter was feeling a little annoyed. He should trust them more; let them in on these kinds of things. Luffy was always preaching about nakama, and yet he wouldn't even tell them about this one, tiny, insignificant secret for fear of being judged?

Usopp was gonna put a stop to this right now.

He pushed his way out onto the deck, heading straight for Nami's cabin. It was a cool night, dark and sweet – he probably would've observed the waves from the front of the ship had he not been so distracted by his frustration. So instead of admiring the scenery, he silently crossed the two doors, not stopping to gaze upon the clear sky.

He didn't knock. Instead, he simply pushed the door ajar, peeking in first in case he accidently disturbed them to the point of ruining a map. As much as Usopp felt left out of the loop, he knew how difficult Nami could become should one of her maps become tarnished.

And, lo and behold –

No one was there. It was empty.

Usopp frowned. That was now two of the crew members unaccounted for. What the hell was –

"Mmm, just like that…"

The quiet murmur had carried over through the breeze and hit Usopp like an anvil. Slowly and deliberately, he turned around to glance at Merry's head – there was a dark silhouette there, too big for it to be merely Luffy.

Well, that solved that mystery. The two were probably chatting on top of Merry's head. Once again though, the secrecy… why with the secrecy? They talked all the time in the day anyway, and it's not like it was some big crime to –

"Damn, you're good at that… Captain…"

Usopp shivered, although the breeze had died down moments ago. That – was Luffy's voice. Who the hell would the Captain be calling Capt –

"So you like that?" Nami's voice asked, husky and breathless. Usopp crept forward, the nagging feeling that had been gnawing at him slowly growing larger as the moon, previously out of sight via some conveniently placed clouds, finally managed to break from its cover. Light illuminated the deck, giving Usopp full view of just why the two had felt the need to keep it between them.

Well, for one, at least they're clothed… was the first thought that drizzled into Usopp's dazed mind.

Luffy was pressed down against the top of the ram head, with Nami's hands firmly weighing down on his shoulders. She had taken the straw hat and placed it on her own head, but Luffy didn't seem to be complaining. Nami, scantly clothed in a silvery night gown, was lying against Luffy's prone form in a very suggestive way. And the number one giveaway that Nami wasn't teaching Luffy how to draw maps?

They were locked at the lips, the feverish exchange urgent and devouring, but at the same time playful and teasing. For all the cluelessness Luffy displayed, he seemed to know his way around that business pretty well. Then again, this wasn't the first time Luffy has acted a little different during the day – strangely enough, that business had ended when they said good bye to Vivi at the end of that adventure. Strange… strange indeed.

As shell-shocked as Usopp felt at finding his captain and navigator making out in the dead of the night – on the pride of Merry, for God's sake! – he couldn't seem to pull his eyes away and scream like he knew he wanted to. They were just so… close. Hands were wandering, moving up and down skin with a soft profession that he just couldn't approve of, and the adoration and fervor displayed in Luffy's dark eyes – for Luffy's, from Usopp's position, were the only ones he could read – was something unreal. It was simply…

He couldn't find the word. Luckily, before Luffy could get to the point where he began to slide Nami's slip down like he seemed to be approaching, Usopp found enough energy to cough loudly and call out,

"I knew from the start. You guys were so obvious."

Of course that was bull. If anyone was giving anything away it had to be Nami, strangely enough – but that provoked the idea of Luffy being experienced in the area of concealing these night exchanges from the group. The only way the situation could get any scarier would be if Robin joined the fray, although Usopp was fairly sure that was not happening.

Nami drew in a sharp breath and swiftly pulled away from Luffy's face, while the Captain followed the movement, leaving Nami sitting in Luffy's lap – a position she seemed remarkably comfortable in. At this point, Usopp was betting it was just sheer familiarity – then again, he didn't know what to believe anymore.

"Usopp!" The two gasped in unison, both faces astonished while not yet lucid enough from their hypnotic actions to offer anything more comprehensible. Usopp smirked and stepped into the moonlight, the closer proximity giving him a better view of how flushed the two looked, and how the thin straps of Nami's dress had just been flicked off her shoulders, leaving only the slender, creamy shoulders that Nami rarely covered with her scant outfits. Luffy's nightshirt had been dropped on the floor of the ship, long forgotten.

"Heh. So much for your secrecy."

"You can't tell anyone!" The two burst out, once again at the same time, before turning to face each other in order to exchange bewildered glances. Usopp also looked a little unnerved by the synchronization.

"… how much did you see?" Nami started slowly, hesitant. Usopp crossed his arms.

"Doesn't matter. Seeing you two right now is enough to tell me exactly why you two have been so lovey-dovey as of late."

"Lovey-dovey?" Luffy groaned. "But you're the only one that noticed, right, Usopp?"

"I don't know," he began, truthfulness shining through his words for the first time since he'd exposed himself, "Zoro seems to be noticing something different between you two, but he's not as clever as me, so he might be a ways behind."

Nami and Luffy both looked embarrassed, but relieved at the same time.

"So, yeah – now you know… why we've been acting a little unusual lately…" Nami coughed into her fist. Luffy slowly pushed them off their perch, pulling Nami into his arms on the way down before releasing her when they hit the floor of the ship, leaving the girl looking oddly… incomplete.

"Sorry guys, but the crew deserves to know. You can't keep secrets! This place runs on the trust we place in each other."

"Never thought I'd hear Usopp complaining about dishonesty…" Nami muttered, subtly moving a little closer to her counterpart while said pirate rubbed the back of his head, having yet to retrieve his hat from Nami.

"You're right, I know it was wrong, but Sanji would be really upset… and it just seemed like you guys wouldn't approve – I don't know," Luffy mumbled, running a hand through his dark hair. Nami looked up at him, offering support through the simple chocolate gaze. Usopp watched the exchange, a little awed.

"You should give us more credit. You and Nami? That's big, you know. Plus, who would've thought she'd settle for someone like you?" Usopp raised any eyebrow, attempting to get a rise out of their captain. It didn't work, as all he did was grin sheepishly and aim a glance at the woman in question. It astounded him sometimes – he was called an idiot more in a day than Chopper probably breathed, and yet he'd managed to land a girl like her. The Devil's luck clearly accompanied his Devil Fruit ability very smoothly, after all.

Nami was the one to take the bait. "Hey, in his defense, he is gonna be the Pirate King."

At this, Luffy laughed while one large hand landed on her head in order to steal his hat back. He put it in its rightful place on his own head, murmuring down at her through the corner of his mouth, while keeping his eyes firmly off the perfect figure,

"That's right. And only the Captain can become Pirate King, so I guess you'll be returning that title to me. Captain wears the hat."

"No fair!" She whined. "I'm the Captain!"

"Not anymore–"

"Hey, come on!" Usopp clapped his hands, jerking their attention back to him. "I'm right here you know! Get back to bed, you two, and we'll talk about this in the morning!"

Nami sighed in a resigned way, making her way back to her cabin. Luffy stayed put, leaning down to swipe his pajama shirt. He glanced from where Nami had paused in realizing Luffy had yet to move over to Usopp, who was looking expectantly at the dark-haired teen.

Slowly, as if not sure he could get away with it, he began to follow Nami, sending looks over to Usopp the whole time. At first, Usopp didn't quite understand what he was doing – and then it hit him that the two were discreetly both closing in on Nami's door.

"Hey!" Usopp barked, all traces of confusion gone, "Your own beds, thanks!"

Luffy sighed, mumbling something under his breath that sounded suspiciously like the word "almost" while Nami tried to hide her giggles at his antics. Before he was out of her reach, however, her hand shot out to catch his wrist, pulling him back suddenly and forcing her to stand on his toes so she could press her lips to his ear, whispering teasingly,

"We'll continue where we left off tomorrow, I promise."

Luffy swallowed, turning around to give her one last desperate, hungry look before Usopp caught his other wrist and threw him forward, pushing him through the door that would lead them back to the men's cabin. Nami watched them leave with a coy smile.

"It was about damn time someone caught us."

o0o0o0o0o

Notes: If you recognize this story, then you have a good memory :) I had this story up on my other account for a little while before deleting it, but months later I decided to reupload it here because I love the pairing and wish there was more of it. I hope it inspires you to share the love :) Nami's even prettier after the timeskip, I love her hair long. Please pay mind to that totally not obvious LuffyVivi reference I snuck in there. I'm not actually a big fan of the pairing, but I just thought it could've been if it really wanted to. So I threw that in there to give him a little practice ;)

If you enjoyed, please review. It really means a huge amount! Thank you for reading,

- Taz