30 Days

Prologue: Part I

It is a normal spring day on Whale Island. The sun is shining, the birds are singing, the flowers are blooming, and the people are out doing normal people things.

But when Killua and Gon return to Whale Island from their trip to the enigmatic country known as Aradia, Gon's behavior becomes a little off. He isn't as happy-go-lucky as he always is. He doesn't run outside to fish for hours and hours in the rain like he used to, he doesn't rush to help Aunt Mito do her work, and he doesn't jump around the house like that pogo stick that Killua saw in an advertisement once.

Gon is also not as full of energy. He gets out of bed much later than usual, seems a tad bit less optimistic, and rarely does anything for no reason anymore.

Killua has definitely noticed that the way that Gon smiles has changed. It's less... Gon. His eyes aren't as bright, and his grin isn't as wide. He smiles less and less, and when he does it is stiff, tight-lipped, and almost forced. Killua knows that he shouldn't be so concerned about such a small thing, but it worries Killua to no end nonetheless.

At first, Killua tells himself, it was just that weird hobo we met on the streets. He probably corrupted Gon or something, and I'll need to find him and kill him when I go back to Aradia.

Then, after three more days, he knows that isn't the answer. Gon is getting worse and worse. His personality, his mannerisms, and the way he goes about his life is no longer familiar.

Gon had become a stranger.

"Mito-san," he says when Gon is asleep in his room. "Something is wrong with Gon."

"I know," sighs Mito in reply. "I'm not sure what it is, but it concerns me."

"Maybe we should consult someone about this? Like a doctor or a psychiatrist or something?" Killua asks. He frowns. "We should do something, at least. This is too abnormal."

"We can contact that friend of yours," Mito replies after a moment of contemplation. "What was his name again? Oreo?"

"Do you mean Leorio?"

"Yes, him. He is a doctor now, right?"

"Yeah. Good idea. I have his phone number, I'll call him."

With a sigh, Killua takes out his beetle-shaped phone and dials Leorio's number. It only takes three rings for him to answer.

"H'llo? Who's this?" drawls the voice on the other end, followed by the faint noise of shuffling documents and the scratching of a pen on paper.

"It's Killua, duh," Killua deadpans, rolling his eyes. "Don't you have caller ID?"

"Yeah, yeah, but I rarely look at it. Why'd you call me? Are you asking me for money again, because you know I'm gonna say no-"

Killua can almost hear Leorio's scowl.

"Of course not, old man! We have a problem!" hisses Killua (silently--he does remember that Gon is asleep).

"Really? Do tell."

"Well, Gon is acting weird lately-"

"Doesn't he always act weird?" Leorio interrupts. His patience is as thin as always.

"Shut up. He's not acting like Gon, and it's worrying his family and me. He may be changing into a sort-of-not-really Kurapika. And I know it doesn't sound that bad since you have a thing for Kurapika, but you'll see."

He hears the bespectacled man wheeze and drop his pen. "O-oh? Bring him over tomorrow—any time is fine." It's clear that he is avoiding Killua's remark, but the ex-assassin lets it slide.

After a few seconds of Leorio uncomfortable, off-key humming as he scrambles to search for something, he gives Killua the address to his apartment, which Killua scrawls hurriedly onto a piece of scrap paper with a small frown.

"Okay. Thanks, old man."

"I'm not old!" Leorio complains.

With that, Killua hangs up.

-

Killua, Mito and Gon gather around the door to Leorio's apartment room.

Killua pounds on the doorbell, feeling more impatient than Mito when she's trying to get him to help with chores.

"Old man!" he shouts. "Open the door!"

"Oi, oi! I'm coming!" Killua hears Leorio complain faintly.

A couple seconds later, the door swings open.

"H'llo Gon, Killua, aunt of Gon," Leorio greets as he smooths out his rumpled shirt. "Come in."

They do so, albeit awkwardly.

Gon and Killua look around, somewhat shocked. Everything is uncharacteristically neat and in place, and there is not a speck of dust on anything. "It's surprisingly clean. I didn't expect that," Gon comments as he lazily moves to sit on one of Leorio's sleek leather couches. "So, why did you bring me here anyway?"

Leorio scratches the back of his neck, searching for an explanation. "Well, ya' see, Killua says you're not feeling too well, so I told him to bring you over so I can have a look..."

"What do you mean?" Gon asks with a yawn, his gaze drowsy. "I feel fine."

Killua, Mito and Leorio all look at each other, as if they are sharing the same thought.

Gon never yawns. Something is definitely wrong.

"Well, do you mind if I check? Just to be sure, you know?" Leorio replies slowly. His brows are furrowed.

"Sure." Gon shrugs.

Leorio rushes over to a nearby oaken table, yanks at the drawer and pulls out a fancy-looking stethoscope. Killua snorts at this. "Is that really necessary, old man?"

Leorio nods solemnly, pursing his lips. He steps in front of Gon as he clumsily inserted the rubbery earpieces in his ears.

"Uh... Mind taking off your jacket?" Leorio asks.

"Huh? Oh, yeah. Sure." Gon shrugs off his favorite forest-green jacket and hands it to Leorio, who folds it neatly and sets it on the glass coffee table.

Leorio sighs. "This is gonna be kinda awkward, I'm sorry."

"No worries..."

Killua notices that Gon is leaning against the back of the sofa, eyes hazy and breaths slow. He is, no doubt, dozing off. Killua's already present frown deepens. "This isn't like Gon at all... he's had enough sleep and everything! Leorio, what's wrong with him?"

"I'm currently trying to figure that out!" Leorio, who is measuring Gon's heartbeat, shoots back in reply. He moves the chestpiece against Gon's slouching form almost frantically.

"His pulse is irregular..." Killua hears him mutter. "He might need to go to a hospital for treatment."

"In what way is his pulse irregular?" Killua asks anxiously.

"It's very quick, and the beat is off. It's a bit stuttery, if you know what I mean."

He knows all too well. He's heard it countless times. 

It was the pulse of someone who was on the brink of death.