"Brother, why won't you see a doctor?" Alluka asked for what seemed to Killua the millionth time.
"I'm fine, Alluka, Nanika, it's just a cold," he reassured his sisters. Though it is strange that I got sick in the first place.
"But you never get sick," she insisted. "And you look really tired. Brother, I'm worried."
"I'm fine, promise," Killua said. He looked tired because he'd been having nightmares, but that was pretty standard fare. He should have been fine.
Killua suddenly coughed harshly, earning a distressed look from Alluka, and after a brief and unpleasant silence, he asked, "Would it make you feel better if I agreed to go get some sleep?"
Alluka nodded, so Killua went to his room.
I feel like crap, Killua thought. What's going on?
As he got into bed, he wondered if he should call Leorio at least, but it seemed unnecessary to bother the old man at a time like this.
xxx
Whenever his nightmares started to get bad, Killua moved himself and his sisters to a hotel where Alluka and Nanika could have their own room so he wouldn't wake them up. This time he did it to keep them from getting sick from him, too. This place had two bedrooms, a living and dining area, and a small kitchen.
Because of this, Alluka and Nanika weren't immediately concerned that Killua wasn't already there when they got up to make something to eat.
As time wore on, they started to worry that Killua still hadn't showed up. It was possible that he had gone out before they got up and hadn't returned yet so they decided to focus on entertaining themselves for a little while longer. However, in the midst of considering this possibility, Nanika noticed Killua's phone sitting on the table where he had left it last night when he went to bed.
Killua didn't leave and he hadn't come out of his room yet.
Alluka and Nanika decided it was time to check on Killua. They softly knocked on the door and opened it a little.
"Brother?" Alluka tentatively called.
Killua didn't answer but they could hear him breathing through his mouth and it sounded like he was in pain. They went into the room and went to Killua's bedside. He didn't seem aware of them and now that they were closer he definitely sounded like he was hurting. They reached out their hand to him and touched his forehead.
He's so hot! What do we do? Alluka asked.
No good. Need request or order.Nanika responded in the choppy way she normally did when she used words.
And I can't do it. Normally, Alluka not being able to make requests of Nanika wasn't an issue but something like this made it a troublesome rule.
The two of them remembered the phone then and rushed back out into the living area and picked it up.
"Brother's doctor friend was...Leorio?"
Alluka spoke out loud while pulling up Killua's contacts. There weren't many and she found Leorio easily.
"Yo, Killua!" Leorio's voice came through the phone sounding energetic and pleased. "You never call! What's up?"
"Um, Mr. Leorio? This is Alluka, I'm Killua's sister," Alluka said.
"Alluka, huh? You're the one who healed Gon, right? Well done! I should thank you! Things were looking pretty bad there for a while!"
Alluka didn't want to take the credit for Nanika's work but Killua had told them it would be dangerous for people to know about Nanika, so Alluka didn't correct him. "So, uh, the reason I called..."
"Is something wrong? You sound worried," Leorio's voice became softer. "Is something wrong with Killua?"
Alluka blurted out everything, hardly pausing for a breath. "He's really sick! He wouldn't go see a doctor and he didn't get out of bed this morning and his forehead is really hot and the way he's breathing sounds like it hurts and I don't know what to do but you're a doctor right? Can you come help him?"
There was a moment of silence and then they could hear what sounded like rustling sounds, like someone quickly gathering their things. "Alluka, send me your location, I'll come right away. Don't worry, okay? I'll help Killua. Your big brother is gonna be okay, alright?" Leorio said, still sounding like he might have been in the middle of packing.
Alluka thanked Leorio and hung up. Alluka and Nanika breathed a small sigh of relief before texting Leorio the name and address of the place they were staying. Leorio texted back quickly,
If Killua's fever is still high, get some washcloths and wet them with cool water and put them on his forehead, one at a time. It should at least help make him more comfortable. Don't worry, I'll be there soon.
Alluka returned to Killua's bedside with washcloths like Leorio had suggested and placed one on Killua's forehead. After something of a flinch, his features seemed to relax and he sighed slightly but he didn't open his eyes.
"Brother?" Alluka called quietly.
"'m okay, Alluka, Na…nika, don't...worry..." Killua murmured. He didn't really seem awake but he was present enough to reassure them and that made them smile.
xxx
Leorio arrived that evening and immediately went in to check on Killua.
"Has he been awake at all today, Alluka?" he asked as he checked Killua's vitals. "Has he eaten or drank anything?"
"He was talking a little for a while and I was able to get him to drink some water then but that's it," Alluka said. "There was a while where he was talking in his sleep too and he seemed really upset, like he was having a nightmare. He wouldn't wake up though…"
Leorio heard the worry in her voice and stopped what he was doing. He knelt down in front of Alluka, put his hands on her shoulders, and said, "I won't let anything bad happen to Killua, got it? Your big brother Leorio is gonna take care of everything, okay?"
Alluka nodded.
"Have you had anything to eat or drink today?" he asked.
Alluka nodded. "I got some snacks when I came to get Brother water and I ordered lunch like we usually do when we stay in for the day."
"You're a good kid, aren't you?" Leorio said with a grin, patting Alluka's head. "Better than your stubborn brother here at least."
She giggled at his praise.
"Why don't you get some dinner while I finish my exam?" Leorio suggested.
Alluka agreed cheerily and left the room to make herself something. Leorio's presence and confidence had clearly put her more at ease and both of them were happy about that.
Leorio continued his examination of Killua, pausing to change the towel on Killua's forehead. When Leorio laid the fresh towel on Killua's head, Killua stirred and his eyes opened part way.
"Killua? Can you hear me, buddy?" Leorio tried to get Killua's attention. "Can you tell me how you're feeling?"
"Like crap," Killua answered, though he still seemed out of it. After a pause, with confusion on his voice, Killua said "Leorio? Wait, where's Alluka? Did she…"
Killua fell back to sleep as suddenly as he has woken up.
"Your little sister is fine, man. Sleep it off," Leorio reassured Killua even though Killua wouldn't hear him.
xxx
"How is Brother?" Alluka asked when Leorio came out of Killua's room.
"It looks like he's going to be okay, but his fever is still pretty high, so I think I'm going to keep an eye him tonight," Leorio said. "It seems to just be a nasty cold though. He should pull through just fine."
Leorio had only told Alluka part of the truth. Killua did have cold-like symptoms but that wasn't the root of the problem. Killua actually had a form of Nen poisoning that was at the time being called Distress Induced Nen Toxicity but was often colloquially referred to as a Nen cold due to the cold-like symptoms it usually presented with. His Nen was turning toxic because of something deeply upsetting him and it was poisoning him. It seemed Transmuters were especially vulnerable to the disease. Leorio knew how to address Nen colds in theory, but each case was different and getting Killua to open up about his feelings was certain to be difficult.
Something must have been really eating at Killua for it to get this bad. Nen colds normally arose from significant emotional distress or troubled thoughts, and the fact that Killua hadn't had a Nen cold before meant he had a high tolerance for that sort of thing, unsurprisingly.
However, the Nen cold meant that the nightmares Alluka noticed were going to get worse before Killua got better. He needed to let out what was upsetting him and, ideally, resolve it.
Leorio wondered what could possibly be the issue causing Killua such a huge amount of distress or pain. Did it have something to do with Gon? Or with Killua's childhood? Illumi? The Chimera Ants?
"Mr. Leorio?"
Alluka's voice interrupted Leorio's reverie.
"Is something wrong, Mr. Leorio?"
"Just Leorio is fine," he said with a smile, patting her head again. "And no, everything is fine."
Leorio stayed up with Alluka a while longer before suggesting she go to bed. She agreed to so he walked her to her room.
"Do you want me to tuck you in? Or tell you a bedtime story?" Leorio asked.
"No, I'm fine," Alluka responded. "Brother likes to do it but I'm used to going to bed on my own. No one ever really did that for me when I was growing up after they…Um, just look after Brother, okay? I'll be fine!"
"A-alright," Leorio said, feeling off balance the way he often did when he heard about Killua's childhood on occasion. "Sleep well, Alluka. I'm gonna watch over your brother tonight. It will be fine."
"Okay!"
"Good night."
After Leorio closed the door to Alluka's room, he had to take a moment to collect himself. The thought of the amount of neglect and violence that must have gone into Killua and Alluka's childhoods was difficult to stomach.
He eventually succeeded in pulling himself together and wiped his eyes and went into Killua's room to watch him for the night.
xxx
"Gon...don't go."
It was very late and Leorio had dozed off slightly when he was roused by Killua talking in his sleep.
"Gon...don't make me leave him. I don't want to leave him! Gon! "
It was easy to forget that Killua was still a kid but the pathetic whine he let out upon waking from the dream reminded Leorio that his very scary and very talented assassin friend was, at the moment, just a sick young boy. It was the kind of whine that children, spent from sickness and fever, let out when they encounter any negative emotion in their semi-delirious state of exhaustion.
"Killua, stay with me, buddy," Leorio said. "Listen. You have a Nen cold. You need to work out what's upsetting you so much or you aren't going to get better. Your mental state is making your Nen poison you."
"I'm fine, I'm immune to poison," Killua grumbled.
"Yeah, yeah, and you can't feel pain either, right?" Leorio retorted.
"...It's not that it doesn't hurt but it doesn't bother me."
"Uh-huh, that's what I heard. And anyway, this isn't like a regular poison, it's not just in your blood or in your digestive system, it's your Nen. You're not gonna just will yourself through this so come on and spit it out."
There was a stubborn silence from Killua before Leorio said more kindly, "Hey, man, it's not like I'm gonna judge you. What could I even judge you for?"
The feeling in the air changed as Killua relented.
"Promise me," he said.
"Huh? Promise?"
"You won't tell anyone. Not Alluka, not Gon, no one. Promise."
"I got it. It's a promise."
Killua told Leorio about their misfortune investigating the chimera ants initially and how they had been told to defeat two assassins, Knuckle and Shoot, before being allowed back to the NGL to rejoin the ant hunt. He brought up how Palm had gotten in touch with Bisky and brought her in to train the boys. Killua said they had trained with Bisky for a month to work up to the task.
Killua stopped talking and curled in on himself slightly. Leorio guessed they were getting to what was bothering Killua.
"The night before our last chance to fight those guys, I did some special training with Bisky while Gon slept," he said, voice sounding tight. "She told me that the way I had been trained to fight made me weak. She told me that because I always fight looking for a chance to escape that one day...I would...leave Gon behind to die. She said if I couldn't overcome that and defeat Shoot, I had to leave Gon's side. I've never felt so terrified of losing something."
"Wait a sec," Leorio interrupted. "I thought you said you were fighting this guy the next night! Isn't asking you to overcome years of training overnight asking too much?"
Leorio didn't doubt the truth of Killua's words in this state, too out of it to hide his feelings and lie, but this was starting to sound ridiculous. What kind of sadistic freak teacher would impose that kind of rule?
"I lost. I couldn't defeat him. I kept trying to run away no matter how hard I tried to fight against Illumi's voice in my head," Killua continued. "I couldn't stop thinking about what Bisky said and what Illumi taught me. We only fought for a couple of minutes before I totally lost my nerve and gave up. I was weak, just like Bisky said."
"Now hang on," Leorio tried to interject. "You're not weak, hell no! And asking you to break through the brainwashing your family forced onto you your whole life in one night is totally ridiculous! It's outrageous!"
"She knew. She could see I wasn't good enough for Gon," Killua said. "I've always known it, I just didn't want to believe it. My brother knows it, Bisky knows it, anyone with eyes can see it! But I-!"
Killua sounded anguished as he cried out, " I didn't want to leave Gon! I love him and he's my best friend . But I can't do anything for him. I just put him in danger I can't protect him from."
Killua only managed to cry for a few moments before the combined excess snot from his cold and his crying dislodged and hit his throat, triggering a coughing fit. Leorio sat Killua up and leaned him forward to rest his torso on Leorio's arm so he could cough out any mucus that came free more easily. Killua coughed a few more times before leaning heavily into Leorio and letting out a couple more sobs.
"Wanna hear the worst part, Leorio? I found one of Illumi's needles in my head later. He'd been there literally inside my head that whole time. I wasn't ever gonna be able to beat Shoot like that. I didn't even notice it until I was fighting this ant later. Gon didn't have his Nen and if that guy had beaten me, he would have killed Gon. But I didn't realize the needle was there until I needed to fight against Illumi's influence so badly because if I didn't Gon was actually going to die ."
Killua voice betrayed how defeated he felt when he said, "It's why I left Gon. I'm...not going to see him again. I miss him so much but I don't deserve it. I don't deserve to be his friend. Everyone is right. Bisky just gave me the reason."
Leorio shifted Killua into a supportive hug. "Hey, man, you know Gon considers you his friend no matter what, right? No matter what that Bisky asshole said, no matter what your creepy brother said, Gon cares about you too. You should have seen what he did to Illumi when he found out what he said to you about not having the right to be his friend. He came in and ripped that guy right out of his chair and held him over his head, crushed the bones in his forearm too. Told him he didn't have the right to be your brother. Gon is a hell of a kid and you're really important to him."
"Don't tell anyone," Killua said, sounding like he was drifting off again. "Don't tell…don't tell Gon…. He'll come find me…. He'll start a fight…with Bisky…."
Leorio had been paying attention to the state of Killua's Nen since he started talking and was relieved to notice it becoming slightly more stable and less toxic. Leorio laid Killua back down as he continued muttering and waited for him to fall asleep before allowing himself to doze as well.
He needed to go shopping tomorrow.