As she said that, the Nen on her fingertip disappeared. 

"Wait, Senka. Are you really planning to show them everything?" Ryu, who was slouching by a nearby tree, stood up straighter.

She gazed at him with a finger to her chin. "Why not? It'll be easier to explain since we're gonna be training together for a while, right?"

Ryu sighed. "Well, yeah... might as well."

"Right?" Senka grins, before turning to you three with that mischievous smile from earlier. "As I was saying–" She snapped her fingers.

As she did, spheres of bright yellow Nen appeared on the trees bordering the small clearing you were in. 

"No wait... they're not spheres..." You widen your eyes, taking a closer look on the Nen by one of the branches. "They're more oval-shaped?? No wait..."

"They look like eyes." Killua uttered, gazing at the others as well with widened eyes infused with Gyo. "I don't see any nen connected to Senka though... does this mean–"

"Yup! It's an Emitter technique!" Senka grinned, placing her hands by her hips. "These blobs of Nen are like my eyes! I mean... they're even shaped like my eyes!" She laughed heartily. "I call this ability Wandering Eyes, and it lets me see what they're seeing," she says. "This is what I use to gather information. To figure out where our targets are and what they're doing. I can attach them anywhere, and keep them hidden with In. Since they're Nen that's been separated from me, I could potentially watch from any distance." As she said that, a more serious smile touched her lips.

Killua smirked. "I see. For someone as loud and short-tempered as you, Senka, I wasn't expecting an ability like that."

"Huh? WHO ARE YOU CALLING LOUD AND SHORT-TEMPERED??!!" Senka exclaimed, grabbing Killua by the collar as a visible irk mark appeared on her forehead.

You could feel yourself getting anxious as you waved your hands in a panic, trying to stop her. "Senka! Calm down!" You exclaimed, stepping in between them.

Alluka pouted, a petulant frown overtaking her features. "Senka! I told you not to pick a fight with Onii-chan!!" She put her hands to her hips.

Her fury quickly faded away as she took a sharp inhale, letting Killua go. 

While Killua nonchalantly recovered from Senka's outburst, she looked away, clearing her throat. "Ehem! So anyways, that's my Nen ability!" She put her hands to her chest, while the rest of you sweatdropped after her sudden outburst.

"Since you have a bunch of these Eyes all around this clearing, does this mean you can see everything from every angle?" You asked, looking at each of them on the tree branches.

"Yup! I have about 20 of them lined up!" She exclaimed, suddenly back to her cheery self as she turned to you. "So anything you do while my back is turned, I'll still know as long as I'm using this ability!" 

Alluka's eyes shone with awe. "That's such a cool ability, Senka! You have so many, too!" She looked around in awe. "They're like lights from afar!" 

Another hearty laugh erupted from Senka. "Thanks!" She smiled. "As you could already guess, I have some around the shore, too. We're pretty far from it though, so I can only place around 10 of these Eyes." 

"So if someone comes to this island, you'll know." Killua put a hand to his chin. "I see, so your ability keeps this island defended somehow." A small smirk touched his lips as he rested a hand by his hip. 

"Yup! I can see pretty far out too, so we won't have to worry! Right, Ryu?"

"..." 

"Huh? Ryu?" Senka turned to Ryu, wondering why he wasn't replying. "AH! WHY ARE YOU SLEEPING??!! WAKE UP!!" She shook Ryu by the shoulders, who was sitting by a tree, fast asleep.

Ryu stirred, sluggishly opening his eyes. "Huh...? Oh, it's you, Senka," he deadpanned, as he yawned and stretched. 

"Did you even listen to what I was saying earlier??!!"

"Huh? Nope." He yawned again, standing up. "I already know how your ability works and all. There's no point." 

"WHAT DO YOU MEAN THERE'S NO POINT??!! HOW COULD YOU SAY THAT??!!"

_ _ _

"Ahem! So anyways..." Senka cleared her throat once more, calming herself down. "As you can guess from the nature of my Nen, I'm an Emitter. Meanwhile Ryu–" she nudges Ryu with narrowed eyes. "–Is an Enhancer. So his main ability is heavily based off of Ko." 

"Ryu's an Enhancer, huh?" Killua's eyes widened slightly. "Never would have guessed."

Senka burst out laughing. "RIGHT?! I've never met an Enhancer like him before!" she exclaims, slapping Ryu on the back.

"Ow–"

"Hey, why don't you show them your ability, too, so it's fair?" Senka suggested, smiling at Ryu. "Oh wait... it'll be easier to show during training, though. Nevermind!"

Ryu sighs deeply. "You're a handful, sometimes, you know?"

"Huh?! Same to you!!" Senka pouted.

Ryu turned away, his eyes eventually landing on Killua. "Oh right... I was wondering something about you," he states, narrowing his eyes slightly. 

Killua blinked. "About me? Sure, what's up?"

"You're a Zoldyck, aren't you?" He buried his hands under his hoodie pockets, gazing at the trees. "An assassin like you doesn't have to be doing these things, so–"

"I'm not an assassin." Killua cut him off. "I'm a hunter who decided to help this idiot." He ruffled your hair.

"Hey–"

"I may be from an assassin family, but that's about it." Killua placed his hands behind his head, turning away to look at the trees as well. "I won't be going back there."

For the first time, you could see the corners of Ryu's lips tug upwards in a smile. "Good to know."

Senka's eyes widened, noticing Ryu's expression, but she quickly brushed it off with a laugh, leaning her arm against Ryu. "Man, you ask weird questions sometimes, you know?" She says, smiling at a now poker-faced Ryu.

"I had it in my mind for a while."

"I know, I know," Senka smiled, patting him on the back and turning to the three of you once more. "I would ask you to show your current Nen as well, but we can save that for later." Her dark eyes somehow got even darker as she smiled mysteriously. "If we're working together. You need to be able to keep up with us," she starts.

Killua raised a hand. "You won't have a problem with that. We all had Nen and physical training."

"Oh? I wonder about that." Senka smirked, nodding at Ryu. "Let's test it out, shall we?"