The Going Merry sailed smoothly through the Grand Line in a rare moment of serenity. It had been over a day since the Strawhats had escaped the marine blockade, and they were still adapting to the relatively relaxing endeavor of sailing without incident. Looking back, their time since coming to the Grand Line had been wrought with danger, and while their adventure happy Captain and adrenaline junky First Mate had no problems with it, the rest of them were enjoying the sudden lack of tension.
"Hey Usopp!" Luffy shouted excitedly. The sniper turned from where he was working on his weapon designs to face said captain, and saw with much mirth that he had hands growing out of his head, which closely resembled horns. "Look, I'm a tanuki!"
Chopper, who was watching the scene, immediately took offense. "You mean a reindeer! Tanuki don't have antlers!" Luffy and Usopp fell over laughing at Chopper's expense, which only made the doctor angrier.
Luffy controlled his laughter and addressed Chopper's objection. "Of course they do Chopper. I mean, why else would you have antlers?" he asked.
Chopper easily rose to the bait. "Because I'm a reindeer!" he shouted indignantly. This time, Luffy looked at him like he was in idiot.
"Are you stupid Chopper? Reindeers don't walk on two legs," Luffy replied. Chopper's jaw dropped upon hearing the logical fallacy.
"NEITHER DO TANUKI!" he shouted, too gullible to realize that Luffy was doing this intentionally. Usopp, who had just gotten up, fell over laughing again, while Robin let out a laugh of her own as she watched in amusement.
Luffy paused to consider Chopper's argument. "Hmm, you're right," he acknowledged. "I guess you must be half human half tanuki then."
"I'M HALF REINDEER!" Chopper yelled, waving his arms up and down as if he was throwing a tantrum.
Luffy's eyes lit up in comprehension. "Oooohh! So you're half reindeer half tanuki half hu-" Luffy was cut off from his calculated taunting as a hand bloomed out of his shoulder and covered his mouth. Luffy turned to Robin and pouted. She smiled innocently.
"Sorry Captain-san. But Longnose-kun is going to pass out from lack of oxygen soon," she said as the hand disappeared.
Luffy turned to Usopp, who was gasping for air, and smiled sheepishly. It was then that Sanji announced that he had snacks ready. Usopp rushed toward the kitchen, Chopper following behind him. Luffy, surprisingly, didn't go. He stared toward the kitchen longingly but instead turned to Robin, who looked back at him curiously.
"There's something you've wanted to ask me since we left Alabasta," he said, not beating around the bush. Robin blinked, surprised by both his directness and his observational skills. She liked to think she was good at concealing things like that from the attention of others. It was one of the skills she had developed over the years. And yet in the brief encounters she had had with her new captain so far, he had always managed to read her somehow. If any of her previous superiors had ever shown that capability, it would have been a cause for concern. Crocodile had been good, but not this good. She would have been dead long ago if the warlord could tell what she was thinking this easily. And yet, for some reason it didn't really bother her that Luffy could see more than what she generally allowed people to see.
The scary part was that she knew it should.
"There is," she responded. "A few things, actually."
Luffy smiled good-naturedly. "Well, you can ask whenever you feel like it. We don't care that much about formalities on this ship."
Robin nodded slowly. She had expected as much, but old habits died hard. "Captain-san, I don't want you to take this the wrong way, but I was wondering why you invited me to your crew," she said carefully.
"Are you happy here?" was Luffy's immediate response. Robin didn't even hesitate before nodding.
"I haven't been with you all long, but yes. Happier than I've been in a long time," she answered.
"Well that's why," Luffy said simply. As much as Robin's heart wanted to accept the answer, her brain urged her to probe for more information.
"But why would you go to such a length for me?" she asked insistently. Luffy smiled at her again.
"Robin, you're always trying to see passed the outer layer of everything. I'll admit that's an important thing to do, but in this case you're looking for hidden meaning that isn't there. I know that you're a good person who was dealt a bad hand, and that it drove you to do things you regret. I wanted to make you happy for a change. That's really all there is to it."
Robin stared at him wide-eyed. As far as she could tell, he wasn't deceiving her. He meant every word. The idea of someone striving to make her happy without any ulterior motive was so utterly foreign to her that she wasn't sure what to do with it.
"Thank you, Luffy," she said quietly. She had broken out of her formal habits and addressed him by his first name, immediately causing his grin to widen.
"So you said you wanted to ask something else right?"
Robin nodded, quickly gathering her wits. "I noticed that you seemed to know beforehand what the poneglyph in Alubarna would reveal. Is there a reason for that?"
Luffy paused for a moment, thinking about how to something like that to Robin. He wasn't going to lie, but he wasn't going to tell her the full truth either. Not yet.
"Captain-san?" she asked after he was silent for a long moment. He rubbed his head sheepishly.
"Sorry, it's just that that's a bit complicated, and I'm not that good at explaining things," he said. "So I'll just give you an explanation that someone once gave me. The first thing you should know is that everything in the world gives off a certain evidence of its presence, one that transcends the perception of the 5 senses we humans use to interact with our surroundings." At this point Robin could tell that he was indeed repeating this explanation from another source, seeing as he didn't normally speak like this. Nevertheless, she eagerly listened, despite wondering where this was going.
"Some people refer to this as a voice. Others call it a feeling. In reality it's neither of those, but people have their own way of interpreting what they perceive." Robin nodded in agreement, and Luffy continued. "For our purposes, let's just say that every object in the world gives off an aura. In living beings, this aura is far more noticeable than in inanimate objects. In living beings that can think and feel, the aura becomes that much stronger. Beyond that, the aura gets even stronger depending on the strength of one's mind. In humans and other animals, the aura is strong enough that people can develop the ability to pick up on it by unlocking a sort of sixth sense. Most people call that sixth sense observation haki."
"Observation haki?" Robin repeated. She was visibly intrigued by this explanation, and decided to forget about her original question until they got to it.
Luffy nodded. "Observation haki is an ability that any sentient being can learn. It may be worth mentioning that Zoro and I can both use this ability. The best observation haki users can sense the presence of any living being if they focus hard enough. But sensing the presence of an inanimate object is an ability that's unreachable to most. Still, there are a select few who are born with an advanced perception and can do it. There's a special name for that ability."
"And that is?" Robin asked.
"The power to hear the voice of all things."
Robin went through the explanation again in her head. It all seemed a bit farfetched. She wasn't one to think she had seen everything the world had to offer, however, and she saw no reason for the captain to lie about such a thing. "Do you know anyone who has that ability?" she asked suddenly.
Luffy grinned. "Well, for starters, me," he replied. Robin simply stared at him, and Luffy finally addressed her question.
"Poneglyphs, for some reason, have a really strong presence among inanimate objects. But it's more than that. To me, it almost feels like a human's aura was somehow ingrained in that stone, but it's diminished to the point where normal observation haki users can't sense it. To a certain extent, I was able to pick up on what it was conveying before I even entered the tomb."
Robin's eyes widened when she heard this. If what he was saying was in any way accurate, the implications were awe inspiring. Could the ones who left the messages of the poneglyphs have left more than one form of link to the Void Century, one that was untraceable to the vast majority of the world? She would have to think more about this.
"Well, if that's all, I'm going to go eat some of those snacks!" Luffy said excitedly as he raced towards the kitchen, leaving Robin to her thoughts.
After the Strawhats ate lunch, Luffy announced that it was time to get back to their haki training, a statement that was met with resigned acceptance to all but Zoro and Robin, the latter of whom raised an eyebrow. "Haki training?" she asked.
"Oh right, new crew member," Luffy acknowledged, before turning to Zoro. "Alright, who has to explain this time?" he asked. Zoro responded by holding out his hand in a fist. Luffy looked amused. "Really?" he asked. Zoro just looked at him expectantly, and Luffy shrugged. The two played rocks paper scissors. Zoro chose rock and Luffy chose paper. Zoro looked down at his hand, wondering what he'd done wrong this time, before shrugging and turning to Robin. Nami's eye twitched.
"All right. There are three types of haki. Conqueror's, armaments, and observation," Zoro began.
"I've already explained observation to her," Luffy chimed in. Zoro hummed.
"Alright then, one thing to know is that not many people can use Conqueror's haki. In fact, only about 1 in a million can. It allows you to overpower the wills of weaker individuals, bending them to your will or even knocking them out. Someone with mastery of this technique can crush armies without lifting a finger.
Robin's eyes widened in comprehension. "The rebel army in Alubarna," she breathed.
Zoro nodded. "Luffy has mastered Conqueror's haki," he said. Robin was dumbstruck. The captain possessed two rare abilities of that nature? What star was he born under?
"But you guys can't use that from what we can tell," Zoro continued, "So the last one to explain is armaments haki, which is basically a weaponized manifestation of your willpower. It's allows you to coat yourself or an object in an invisible suit of armor that strengthens both attack and defense. It also lets you bypass some devil fruit defenses," he recited from memory.
"Devil fruit defenses?" Robin asked. Zoro decided to elaborate.
"Crocodile was a logia. His devil fruit let him turn into sand. If you were able to use armaments haki, you would be able to bypass his intangibility and attack him anyway," Zoro explained.
"So that's how you were able to hit him," Robin said to Luffy. "I always wondered if there was a way to counteract those abilities. I guess this would be it."
"That's not all it can do," Luffy said. "Robin, try using your power on Zoro." Robin looked stunned by the suggestion, but Luffy just grinned. "Go ahead, don't hold back. Pretend you're trying to put him out of commission." Robin looked hesitant but complied. She crossed her arms and hands grew out of Zoro's body in an attempt to clutch him. Immediately the sprouted hands were blackened to obsidian, and much to Robin's shock, she couldn't move them. Upon further inspection she realized that her real arms were also blackened and completely immobilized.
"What is this?" she asked.
"That's armaments hardening," Zoro said. "It's an advanced form of armaments haki that can be applied to solid objects. When your arms came in contact with me I used it on them. Since my armaments haki is a physical manifestation of my will, it overrode your control of your limbs," he explained. "Against someone who doesn't know any armaments haki, doing that is fairly simple. If you could use it to an extent, it would be harder, and if your armaments haki was equal to or stronger than mine, I wouldn't be able to do it at all."
"This seems like an extremely useful ability," Robin commented.
"All three types are," Zoro replied. "But most people have a natural disposition towards one of the types. Luffy's is Conqueror's, and mine is armaments. If I had to guess, I'd say yours is observation."
"How would you know that?" Robin asked.
"Your aura, your personality, and your fighting style are all big indicators," Zoro responded. Robin nodded in acceptance. After that, Zoro explained the many uses of observation haki. When he mentioned that sensing emotions was one of them, Robin's eyes widened slightly. Outwardly she showed no other signs of it, but inwardly she just realized why Luffy could read her so easily.
The rest of the day was spent training in armaments and observation haki. Robin was able to pick up on the fact that they had been doing this for a while but were having little to no progress. Despite this, Robin found that she wanted to participate. It wasn't so much that she thought she could learn the techniques or even had a deep desire to. It had more to do with her desire to take part in the endeavors of the Strawhat crew.
It was starting to get dark, and most of the Strawhats were calling it a day. Sanji, on the other hand, had wanted to keep going, determined to make at least some headway. The chef was currently blindfolded and was working on awakening his observation haki. This essentially involved Zoro standing behind him and hitting him over the head with a stick. Robin could tell that he was getting more frustrated after every hit that he failed to dodge. He had been at this for long enough that he had actually figured out a pattern in Zoro's consecutive swings and had started dodging based on that, but the swordsman had quickly caught on to what he was doing and switched up his pattern.
A loud thwack signified that Sanji had yet again failed to predict one of Zoro's random swings. Luffy was trying hard not to laugh as Sanji rubbed his head in barely withheld frustration.
"Hey cook. You need to dodge or else you'll get hit by the stick," Zoro said unnecessarily. Despite not being able to see him, Sanji turned to him in outrage.
"No shit, dick with a stick!" he shouted, causing Luffy to burst out laughing and Zoro to hit him again for good measure. Sanji was grumbling something about shitty swordsmen and their sticks when Zoro swung again.
Only this time Sanji moved his head out of the way. Luffy stopped laughing and looked at Sanji with widened eyes while Robin looked on curiously. He was still blindfolded, and Zoro's attack had not followed any particular pattern. It really had seemed like some form of precognition.
Zoro smirked. "Hey cook, why'd you dodge?" he asked.
The question seemed to infuriate Sanji, who spun around again. "Because I didn't want to get hit you shitty moss head!"
Luffy started laughing again, and Zoro seemed annoyed at the return of the nickname he hadn't heard since his previous life. He stifled his annoyance though.
"What I meant was, how did you know you were going to get hit?" Zoro asked.
"Because you were-!" Sanji stopped mid sentence and thought about what he was about to say. Because you were thinking about swinging. Although he was blindfolded, none of his observers missed the comprehension that dawned on his features, followed shortly by the look of triumph.
Sanji had awakened observation haki.