A/N: Erm…I like to write people's opinions of relationships. So this just popped up in my head. Hope you'll enjoy it.

Oh yeah, this fic has ZoLu. I know I write about Zoro and Luffy a lot, but that's because I'm a die-hard fan!

Robin sipped her coffee and watched the scene unfolding before her. Her crew members don't seem to know what's going on, with the exception of Nami, who likes to know everything that goes on in the ship. Chopper noticed but he seemed confused. The others were just plain oblivious.

Zoro was doing push-ups. Luffy was sitting on his back, tracing little circles in his first mate's torso. He looked bored and mumbled something. The swordsman stopped and flopped onto his back, nearly sending Luffy to the floor if the younger boy hadn't stood up in time.

Luffy was about to walk away, thinking the green-haired man had finished his training when Zoro grabbed his wrist and pulled him down. Luffy went down with a yelp, landing on the swordsman's body.

Zoro growled something and Luffy just grinned and laughed. Zoro's scowl deepened. He asked something and Luffy stopped laughing. The rubber pirate wore a serious and thoughtful took as he thought about something. Then he answered his first mate's question with a big smile on his face.

The swordsman's scowl softened and he reached up to thread through Luffy's hair. Luffy leaned down and gave Zoro a quick kiss on the lips. It happened so fast that none of their nakama near them caught it.

But Robin saw it. She smiled. However, she did wonder why her crew members (excluding Nami) didn't notice what was happening right under their nose. She had noticed it within a week when she joined the Straw Hat pirates. Besides, Zoro and Luffy didn't really bother hiding their relationship anyway.

Their entire relationship was something that everyone wanted in their life. They trusted each other with their lives. If Luffy gave an order, no matter how ridiculous or crazy it is, Zoro would still do it. It's incredibly rare to find such love like that.

Robin thought on how strange it was for a pirate hunter to join a pirate, and as first mate too! They were practically opposites. And yet…they were the same. The same in what? Robin wasn't quite sure.

Perhaps it was their constant and determined pursuing of their dreams. Or maybe it was their outlook on life, always straightforward and true. It could be their complete understanding of each other. Or it could just be the fact they're always provoking Sanji's temper.

Whatever it is, it's complicated yet simple. Simple? Robin mused. Yes, it was simple.

Zoro once lived just to pursue and achieve his dream, to keep a promise to a dead friend. (don't ask how she knows that!) But now…now he has something else to live for, or rather someone else…Sure he'd take a bullet for any of them, Nami, Usopp, Chopper, herself, Franky and Brook (not like the skeleton need protection from a bullet, he 's a freaking skeleton for goodness' sake!), hell even Sanji.

But Luffy…Luffy was different. Zoro would kill himself if that would mean his captain and his dream will be safe. Robin had been one of the few who'd known about the Kuma incident. Luffy was still oblivious about it but that doesn't mean that he didn't sense something had happened while he was unconscious. Anyway, Luffy had told her everything that happened when he met Zoro, so Robin knew what Zoro had told Luffy.

That Zoro would kill Luffy if he ever stands in the way of him becoming the greatest swordsman in the world.

Turns out, that didn't happen. Nope, not at all. It just shows how much Zoro loves and treasures Luffy, as a captain and as a lover. Robin smiled again at the thought.

The both of them just understand each other. Even Robin and Nami, as smart as the two of them are, couldn't tell what's Luffy's planning or even decipher some of his expressions. Sometimes, for the well being and safety of his nakama, he'd do drastic and dangerous things…like recklessly taking on Enies Lobby (Robin chuckled, she's the reason he did that) and using his Gear Second too much. He knew the toll of Gear Second on him, yet he still uses it.

But Zoro…Zoro was different from the rest of them. He'd know what's in Luffy head, like that incident in Jaya. Just one order from his captain and he let himself get beaten up. Just like that. At least that's what Nami told her. He'd just know, you know. It's frustrates Nami a lot. And Zoro just goes along with it. Even if he gets hurt, he wouldn't mind. He's just that kind of person.

Robin had the feeling if Luffy should ever die, Zoro would make sure the rest of them achieve their dreams first and then he'll kill himself. The Risky Brothers had told her everything when she informed them that she knew. They had specifically told her what Zoro's words to Kuma were. And she'll never forget them.

"Luffy must be the man who becomes Pirate King! If I can't even protect my captain's dream, then I'm not worthy to become the world's greatest swordsman!" (A/N:er…am I correct?)

Robin was surprised but not much. She had expected this after all. Zoro wasn't the type to just sit there and watch his captain get killed. She smiled again (!) What a loyal first mate Luffy has.

"Robin? What are you smiling at?" Chopper asked innocently. He was sitting beside the archaeologist, reading medical books, when he noticed her smiling rather oddly.

"Nothing, doctor-san. Just thinking about a relationship between a captain and a first mate."

Chopper frowned and looked over to where Zoro, Luffy and Usopp were, they were playing tag. It was obvious Luffy forced Zoro to play since the swordsman looked a bit disgruntled.

"That's what Luffy and Zoro is, right? A captain and a first mate?" the little reindeer asked.

"Yes, doctor-san." Replied Robin.

"Oh. Is there anything special with that relationship?" asked Chopper, getting curious.

"Very special. If you observe carefully, you might just see why it's so special." Robin turned back to her books. Out of the corner of her eye, she can see the little doctor staring at Zoro and Luffy, trying to make out why their bond is so special.

Robin hid a giggle. How cute.

A/N: it was kinda messy, wasn't it? Pls review. I would like to read your opinion on this. I might do another chapter, then again, I might not.