A/N: Here's the next one for ya. I know this fanfiction is unbelievably close to the main storyline, but I like to keep it as though it were the original show, just with another character thrown in there. It's fun to see how it all changes. Anywho, enjoy.

The Line Between Genius And Insanity Is Paper Thin

"Ahh!" Stasy let out an exasperated sigh as she fell on her back and sunk into the soft cushion of the bed. "Our own room! Feels so nice!"

"What are you doing here, Stasy?" Gon questioned her. "Your room is next door."

The girl sat up and began her pouty face. "Come on, Gon, my cute li'l bro! You wouldn't coldly kick your bigger sister out like that?"

"But we're not related...at all," Gon quirked.

"Stasy, get out of here," Killua kicked her off their bed. "I went through the trouble of arranging you another room, so you better be grateful and take it!"

"But, Killuaaaaaaaaa..." Tears began to form in her eyes. "I think..that...Mel just might come out."

"Who cares," Killua stated flatly, picking her up by her collar and tossing her out. He quickly slammed the door on her and locked the dead bolt. 'That should keep her occupied for a while. I'm sure she'll find some other way in.'

"You're always so mean to her, Killua," Gon paled at the sight of his anger for the girl.

"I don't see why you're so nice to her," Killua rolled his eyes. "Doesn't she annoy you?"

"Well, sometimes, but its the kind of annoyance with feeling," he tapped his chin in thought. "I've never had siblings, so when she says I'm her little brother, it makes me very happy." He gave the sweetest smile to pierce anyone's heart, even Killua's.

The young assassin's face blushed just a bit, before he quickly hid his inevitable heart beat. "Well, if you put it like that, then I guess we're like brothers, so you can treat me like family too."

"Ok," Gon smiled happily.

Stasy ran eagerly to the two boys. "Did you guys see me?" she jumped up and down giddily. "I've never seen so many zeroes in my life! We're gonna be rich!"

"Wait till we reach the 200th floor," Killua snickered, then his face fell serious. "But I'm kinda surprised. The first time I came here, it took me two weeks to reach the 150th floor. We've done it in only 3 days."

"Yeah, but you were 6 then," Gon reminded him.

"That's true, but..."

"Oh! By the way," Stasy piped in. "I saw Zushi on the TV a while ago.

"Me too," Gon replied. "Looks like he's still on the 50th floor. You know, the thing we talked about earlier, the Ren. I wonder what it could be."

"If we go higher, we'll surely meet guys like Zushi," Killua stated.

"Wouldn't it be better if we just asked Zushi?" Gon suggested.

"'Ren' is one of the four basic principles of the big training," Zushi answered them after they had asked. "The four principles of the training are the very basis of every fighting technique evolving spirit elevation and its hardening. Finding the 'Ten', learning the 'Zetsu', succeeding the 'Ren' and reaching the 'Hatsu.' All of these form the 'Nen' practice. That is all." He bowed politely.

"I don't understand anything!" Killua yelled at him.

"Zushi," the calm, commanding voice interrupted their conversation as Wing walked around the corner. "Since when have you become strong enough to teach others? Gon, Stasy, Killua, there's an old saying: 'We understand even less of things when we have half of the information than when we don't have any at all.'"

"'Nothing is more dangerous than half-knowledge', is that it?" Killua perked an eyebrow. "But I want to know, because there's a relation between this and my brother's secret."

"You mean your brother uses Nen?" Wing asked curiously.

"Yes," Killua asnwered. "Would you mind teaching it to me now? Even if you don't, I'l just discover it by myself. But I won't be content with half-knowledge. I want to understand everything. If you accept and teach me, I won't misuse it."

"It's ok, come to my flat," Wing told them as he led them to his home.

When they had been led to Wing's home, they all gathered around the teacher and listened intently.

"What we call 'Nen' has the meaning of 'Inflamming Spirit,'" Wing began his explaination. "We can rename it with the strength of the will. The four mosr important principles are practices to increase the will. With Ten, which means 'the point,' we can concentrate our spirit on one thing, we also think about ourself, and we choose the objective. With Zetsu which translates to 'Language', that thought becomes a word. And then Ren, the 'finishing', enlarges the will and Hatsu, the 'projection', sends the will into motion. The Ren that Zushi used corresponded to the thought 'I won't lose.' But nothing is better than practice. Killua, I think I'm going to kill you. Do you mind?"

"No, no," Killua replied bluntly. "You shouldn't be able to."

"Let's proceed in order," Wing closed his eyes to show his concentration and even took a deep breath. "Ten."

He opened his eyes. "Zetsu. You can say the words in your head or out loud. Either way works." He looked directly at Killua. "I'm going to kill you."

Then all of the sudden, his eyes opened wide into a dark glare and such an oppressively dark aura pushed the children back. Stasy looked around curiously, wondering why everyone was flying back; Gon merely jumped back, and Killua managed to climb up a corner and hide on the wall.

"That was the Ren," the man pushed the rim of his glasses back up the peak of his nose. "If the Ren is powerful, the Hatsu is too. Express your superiority with a cry, and without movement, you'll make your enemy move back. You could also call it a bluff. After some time, the Ren becomes stubborn, and we lose the ability of discerning good and bad things. That's why, if the spirit isn't ready, it's more reasonable to wait. You, as much as Zushi, are in an apprenticeship phase, the formation of the spirit. If you want to learn Nen, you must first be dedicated in Ten. When you've master Ten, you won't be repelled by the psychic aura of your opponent." Wing sat in a wicker chair, hands on crossed legs, smiling business-like. The demonstration was over.

Since they knew they couldn't scower anything else out of the man, they left with a "Thanks a lot!" and began their musing aloud over what they had just learned.

After the children had left, Wing stared at the door for a long time. Zushi came up to his master humbly.

"Sensei, why did you lie?" he inquired of his teacher.

"I didn't lie. I just merely told them enough to fend off any strong opponent. I can't put such a dangerous weapon into their hands yet. Besides, that girl, Stasy. Her Nen flow was quite irregular. It was suppressed, to almost non-existance, unlike the others which were clear and exposed like people who had never heard of Nen. She had the Nen flow of an expert, precisely controlled and critical, unlike anything I've ever seen. That girl actually had an invisible Nen shield around her. That's why she was able to with stand my Ren."

"But she looked sincerely clueless about Nen," Zushi argued. "I really believe she's never heard of it before. Do you think it comes to her naturally?"

"Zushi, have you forgotten the most basic common sense of Nen? Even Nen masters must dedicate some brain power to Nen control, at whatever level. To hold up a sheild and suppress her power so that it was only visible when a strong Nen force was present, such a fiet would require a great amount of concentration and to have it all day round. The average human only uses about 10 of their brain, even when thinking to a great extent. That girl, she must be using about 45 of it daily."

"Is that why she's a little...bird brained all the time?" Zushi chuckled. "The rest of her brain is being used up?"

"I'd like to say that, but...Anyway, let's start on your training, with the Ten formation."