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Heavens Arena. If Killua had truly intended to be discreet about his whereabouts and newfound freedom, he would not have chosen a location that broadcasted his whereabouts in broad daylight. To no surprise, he had gained notoriety in the ring, quickly rising up the ranks and as a result making more noise than Illumi had anticipated from a child who'd all but run away from home a second time.
His father had not asked him to follow Killua. He was not tasked with bringing him home. Until he gave up on his foolish aspirations, it was quite implied that no one in the family was to intervene.
Still— curiosity plagued him.
Curiosity, and something vaguely like concern, and other feelings about the situation that would not be mentioned by name because Illumi Zoldyck was not raised to get worked up over trivial things like personal gripes and emotions.
In fact, Illumi definitely wasn't in Heavens Arena right now to watch his sibling from a distance. He definitely had not come here for Killua. He most certainly had not followed the faint traces of his brother's aura to end up peering from behind a wall as the boy and his new friend stood before a vending machine on the fiftieth floor debating what salty, starchy snack to have for lunch.
"Don't be stupid, Gon, everyone knows shellfish is a disgusting flavour."
"But I'm from a fishing town! I like shellfish!"
"There's no actual shellfish in the crisps, and I'm telling you it's gross!"
"How can they have shellfish chips with no shellfish?"
"Dude, what—"
Interesting. They are fighting already. It has barely been a month. Of course he couldn't have hoped to sustain a friendship. Illumi nodded to himself. Good signs. At this rate, Killua would be home much sooner than expected.
"Mimi? Is that you?"
Illumi blinked, caught off guard at the surprised intonation of a very familiar voice.
And anyway, only one person, ever, called him that stupid nickname.
"It is you," Hisoka snickered with unhinged delight when he turned around with a cold stare. "Oh my, I wasn't expecting to see you this soon. Did you come all the way out here for little old me?"
"No. Get lost."
"Ah, I forgot." A sly smirk that could mean nothing good split his face. He leaned sideways against the wall beside Illumi, far too close. "Gon's little friend is your brother, isn't he?"
Illumi's glare only dropped further down the Celcius scale. No dark aura escaped him, because that would immediately give his position away, but he might as well have directed the full ire of his bloodlust in Hisoka's direction. The magician only grinned with excited anticipation at the unspoken threat. Leaned in, impossibly, even closer.
"Don't worry your pretty little head off about me," he hummed, slowly snagging a strand of silky black hair, twisting it loosely around his pointer finger. "He is the less interesting target of the two."
Illumi slapped his hand away. "Don't even think about hunting him."
"Wow, protectiveness is a hot look on you."
"I am not being protective."
Their bickering was interrupted by the sound of loud banging and clinking, and when they peered over the edge of the wall in almost comical synchronisation, it was to find Killua jamming his entire arm into the vending machine slot while Gon tried to shake their faulty order out of the machine. Hisoka chortled, immediately getting Illumi's hand clapped over his mouth for the noise, which, of course, he immediately licked, a seductive, hooded look from under his lashes catching the assassin in the eye.
Illumi looked like he was about to resort to choking him— which was absolutely not something Hisoka didn't want— when the two children and the vending machine started up their ruckus again.
"Gon, what are you doing?"
"Huh? Oh, I'm putting more coins in! It'll definitely nudge the snacks out, right?"
"Idiot, the whole point is not to be ripped off!"
Illumi blinked at Hisoka, who was shaking so hard from barely held-back laughter. He was so close to compromising this operation already, and if Illumi did not do something now—
He didn't think, he acted. In the back of his mind through experience he knew of one effective way to get Hisoka to shut up, and that looked something like pinning him to the wall and crushing their lips together.
It worked. The impending laughter shuddered to a halt. Illumi felt a surprised intake of breath against his mouth, and then a slow, victorious smirk, followed by hands on either side of his hips.
"Aw, I didn't think you missed me that badly, Illu."
"Shut up," Illumi hissed, glancing back over to where his brother was, this time shouting with glee at the uncontrolled outpouring of snacks from the machine beeping in distress. There was a shout from far away down the corridor— a patrolling staff member– and Killua exchanged a look with Gon, who gulped and nodded his resolve, before they hastily gathered as many bags of crisps and chocolate bars as possible and made a run for it.
"Hey, you! Come back and explain yourselves!"
"Sorry, Mister!" Gon yelled back, sounding genuinely apologetic even while he sprinted after Killua with their questionably-acquired goods. "We'll pay it back once we reach the 200th floor, promise!"
"We will not!" Killua yelled.
"Hey!"
"I can't believe you've never stolen anything before, Gon!"
They disappeared skidding around a corner. The staff gave up, slowing down and catching their breath.
Illumi was only reminded of his current biggest problem when said problem playfully slapped his ass.
"You should have more fun with me, Lulu~"
Hisoka met the full force of his terrible aura with nothing more than a knowing smirk. He wasn't in the least bit fazed.
"That's really turning me on."
"Shut up," Illumi snapped, turning on his heel and stalking down the hallway before he lost to his instincts and fought Hisoka. This was not the time or the place, and it would completely ruin his chances of finding out what Killua was getting up to.
Hisoka caught or dodged every needle Illumi aimed at him while merrily following behind, humming what sounded like the jingle from a toy commercial all the way.
He didn't have much luck with his plan. Killua was elusive enough on his own, and having to keep Hisoka from giving them away didn't help. The familiar head of white hair would always be gone the second after his attention shifted to the magician.
The only time Illumi got to observe him without a problem was through a screen when he fought in the arena. It was exceptionally uninteresting.
"Why?" he wondered out loud.
"Hm?" Hisoka leaned against him with an elbow on his shoulder.
"Why is he wasting his time? His talents are far above this."
A bubble popped way too close to his ear. The sickening sweet smell of pink bubblegum that he'd come to associate with Hisoka assaulted his sense of smell.
"Obviously because he's having fun."
Illumi shrugged out of his reach. "That fight just now did not look fun. If anything, he looked bored."
"That's not what I meant." A sharp nail poked his cheek. Then he pinched his cheek. Hisoka touched him too familiarly— a reality he had begrudgingly come to accept, even though it never got any less irritating. "He has a friend now, doesn't he? Even the most boring assignment can be lots of fun if you have a friend with you."
"Hm."
"Just like when I tag along on your missions sometimes just to keep you company~"
"We are not friends."
"I know, I know, but it's the same principle."
"Stop touching me."
Hisoka childishly poked his cheek. "No."
He would not start a fight here. It was not the time or the place. It would probably also be giving his irritating distraction exactly what he wanted.
"I don't think you'll learn anything new, anyway."
Poke.
"If you stuck around until he reached the 200th floor you might see an interesting fight."
Poke.
"Hey, how about interrogating Gon? Wouldn't that be easier?"
Poke.
Illumi caught his finger in an iron grip that would snap it with any more pressure.
"Fine," he seethed. "I will learn nothing. I am leaving."
Hisoka made an attempt to pull his pointer finger back. It didn't budge. If anything, Illumi's dangerous grip only tightened. Dark, soulless black eyes treated him to the most terrifying and beautiful of glares.
"What about Gon—"
The bone cracked audibly.
Hisoka ended up getting exactly what he wanted, just like every time they did this, finding himself shoved against his own apartment door the minute it shut behind them. Illumi was most fun when he was riled up, pissed off— as much as he liked bringing out that bashful, easily-teased side of the assassin that resulted from being a virgin without even the experience of self-pleasure until Hisoka had ruined him, it was a lot more satisfying to fuck like they were fighting.
And judging by where this was headed, Illumi seemed intent to get back at him for being a pest the entire evening.
Hisoka's grin never left his face, not even when his on-and-off partner sank teeth into his lip hard enough to draw bright, coppery blood that trailed down his chin like drool. He moaned in delight when short, sharp nails pushed under his top to claw his hard abs, drawing blood again, probably, judging by the exciting flash of pain. Illumi panted into his mouth. Pissed off, dangerous.
Hisoka only sought control back from him when he felt a seam on his clothes rip.
"Ah-ah," he tutted, catching Illumi's wrists in one hand— the assassin wasn't a small man by any means, but his shoulders weren't as freakishly broad, his hands weren't as big and his fingers not as slender and endless. Illumi growled at him when he flipped their positions. The assassin's hands trapped above his head against the door, one of the magician's knees in between his thighs. He could tell he wasn't the only one excited about this.
"Let me go," he hissed. His body told a different story, hips rocking to seek friction against Hisoka's leg.
Hisoka ground his knee upwards, pressing into Illumi's obvious arousal, earning himself a sharp intake of breath.
Illumi tried to pull away from the door. Hisoka smirked at him, slowly removing the hand keeping him there.
He remained pinned to it, formidable strands of pink aura making it impossible to escape.
"Bastard," Illumi muttered. From the prominent flush of his otherwise pale white skin, though, he didn't look too upset about it.
"You know what you need to do if you want to stop this," Hisoka reminded him merrily, going to work on the clasps of his pants. He took his cool time getting rid of them.
"Go to hell."
That didn't sound like the safeword, so he really couldn’t be too upset at this turn of events.
To Hisoka's delight, the stoic-faced assassin had positively leaked through his underwear. He pulled it down only midway before sinking to his knees before him.
He didn't usually like giving head– it felt like relinquishing too much of control. He didn't like kneeling for anyone, either. And both those things didn't hold the most pleasant memories from a time he had willfully forgotten.
Illumi was turning out to be an exception to a lot of rules he normally lived by. He was sure that he himself posed an even greater disruption to the assassin's carefully controlled life, so didn't that put them on equal footing?
Illumi's breathing stuttered audibly when Hisoka swallowed him down without preamble. What he didn't take in his throat, he wrapped one hand around, the other settling possessively at the back of Illumi's thigh.
"Hisoka–"
He removed his nen keeping the assassin's hands trapped. Long fingers immediately pushed into his hair, tightening, twisting without any regard for inflicting pain but that was exactly what he wanted. Hisoka moaned unabashedly around Illumi's cock, provoking a full-bodied shiver from the other man he could only feel because they were so close. The hand behind his thigh gripped harder. Illumi shoved him by the back of his head, making him choke, holding this position for five long seconds before he was shuddering and coming down Hisoka's throat.
He might've heard the assassin swear breathlessly, it might have been the ringing in his ears. He swallowed most of it when he pulled away, wincing at the unpleasant aftertaste.
"You do not like it," Illumi observed, sounding exactly a person who'd gotten their dick sucked within an inch of their life. He was, somehow, having greater difficulty regaining his composure after that.
Hisoka pulled a face. "Yeah, no shit. I can taste all that Zoldyck poison training in your jizz."
Illumi blinked, looking mildly startled. "Really?"
Hisoka snorted. "No, of course not. Come here."
Illumi took the hand proffered to him, hauling the magician back on his feet. Between now and when they eventually reached the spacious bed at the center of the room, the rest of their clothes were discarded, with more rough kisses in competition and nails raking skin and hair being pulled. Illumi wrested the upper hand this time, pushing him back onto the mattress and immediately straddling his hips with his whole weight, dragging his mouth down pale porcelain skin and pressing his tongue to the fresh swathes of blood he'd drawn himself.
"I'm going to be on top," he declared, with no room for argument even when Hisoka raised an eyebrow, before clarifying, clearly, since Hisoka was an idiot: "I'm going to ride you."
"I got that the first time."
"You did not."
The corners of his lips quirked up in one of those self-indulgent smirks that were both a source of constant irritation and many distracting daytime fantasies. "Can you choke me?"
"Don't make me do all the work," Illumi stated primly. He looked around them, eyeing both nightstands. "Lube?"
Hisoka chortled. "Honey, you're the one taking the lead here." He lazily pulled a drawer open with a string of aura. Illumi snatched the only bottle inside. The rest of it was cluttered with cards and candies.
That was probably more candy than any of his kid siblings were strictly permitted to have at one time. He briefly wondered what his parents would think of Hisoka. It probably wouldn't be positive.
He tossed the bottle for the magician to catch. "Prep me."
Hisoka popped off the cap a little too ceremoniously, grinning. "Turn around, Mimi."
"Don't call me that." Still, he obliged, turning on his hands and knees. He flinched, just a little, in anticipation as he felt cool liquid on his skin. Hisoka's thumbs spreading him open, a finger teasing his rim.
Illumi sighed, relaxing his body. The initial stretch was not much, and he always started off easy unless they were in a particular hurry. It felt a lot better than his own fingers. It would do too much for Hisoka's ego if he confessed to only ever fucking himself to thoughts of him, though, so that was information Illumi was not prepared to ever surrender.
A second finger joined the first one. Illumi bit his lip and was thankful his partner couldn't see his face at the scissoring motions, when he started fucking him a little harder, a little faster with clearer intent. It was bordering on too much when Hisoka finally pulled out with a kiss to his hipbone.
And promptly slapped his ass.
That pulled a surprised sound out of him.
"What are you—"
"Sorry," intoned the magician, not sounding very sorry at all. "Couldn't help myself."
Illumi glowered at him before turning back around to straddle his hips before he could do it again. He hadn't disliked it, but he was not about to examine that idea. Hisoka had already introduced him to too many of his depraved preferences.
Without further preamble, he gripped his partner's hard cock and positioned himself above it, sinking down to take the entire length into himself until his ass sat flush against the other man's pelvis. Hisoka groaned, though Illumi's forceful grip on his thighs kept him from thrusting before he got used to the feeling.
"Illu–"
"Quiet. It has been a while." He hadn't taken anything inside him since their long night on the airship during the Hunter exam. Illumi shifted a bit more, appreciating the stretch. Committing it to memory, for the next long while he went without.
"Don't move." Hisoka didn't like submitting, but he did love threats. Illumi leaned forward across his chest, wrapping slender, deadly fingers lightly around his throat.
"If that's what it'll take for you to choke me harder," the magician purred, "I am going to be disobedient and fuck you. "
Illumi narrowed his eyes at him. "Then I'll stop if you move or try to take over."
"You got me there."
Illumi tightened his fingers, just slightly. Not letting up on the pressure, he began to move, setting an indulgent and hopefully tortuous pace as he started to fuck himself back on Hisoka's cock.
Hisoka kept his word– with great self-restraint. His eyes grew cloudy, but instead of losing their clarity, he only watched Illumi like his prey. That only made the arousal in his blood and his body worse. He trembled, picking up his pace until the obscene sounds of skin against skin rang loud in the spacious room. Illumi gasped at one particularly hard thrust, lurching forward before Hisoka caught him. His fingers around his neck tightened. Any other person would asypxiate half to death by this point.
Without warning, Hisoka broke their agreement, using just his hips to fuck into him, hard. A breathless yelp punched its way out of his throat and his grip loosened, and then Hisoka was reversing their positions to pin him on his back and haul his legs over his shoulders.
"I loved that," he informed him, so hoarse that Illumi wondered if he hadn't permanently damaged his windpipe. "But I don't want you killing me just yet."
It didn't take too much for Illumi to finish. Hisoka was fast, brutal, just the way he liked this. When he came with a cry of his name on his lips, Hisoka kissed him aggressively and followed soon after, finishing inside. Illumi belatedly realized his nails clawing red lines down Hisoka's back.
Hisoka dropped his forehead down against his, and when their eyes met for a long moment, it almost felt tender. Almost.
"You didn't listen," Illumi commented. It was hard to sound particularly miffed when his chest was heaving and his body still clenched weakly around Hisoka's cock.
Hisoka smirked. "You know me better than that."
Illumi shoved him off with a roll of his eyes. When he sat up against the plush velvet headboard, he felt slick fluid run down the inside of his thigh, cool dampness from the sheets wet with sweat. Completely unasked for, Hisoka dropped his head in his lap, cheek pressed against his thigh as he turned on his side to look at him.
"What's so wrong about it, anyway?"
"Mm?"
"Why are you so mad your brother has a friend?" His expression was completely ridiculous, pouty and curious like a child's.
Illumi didn't need to mull over his answer. "Assassins are not meant to have friends. It will only make us more vulnerable. Furthermore, there will always come a day where we will need to betray them. It is unfeasible. I simply wish to spare him the trouble."
Hisoka grinned slyly. "Will you betray me too, Illu?"
"If it needed to be done, yes."
"Will you kill me?"
A pause. Long enough to surprise Illumi himself. He replied, "If I was contracted to do so."
"Then I want to contract you." Hisoka took his hand, kissing the back of his palm. It felt eerie, this tenderness when this was the topic at hand. "I don't trust just anyone to do it. I won't be satisfied unless I know they are stronger than me or at least evenly matched. And as much as I look forward to fighting your brother's friend when he reaches his full potential, you're the only one I think I can trust with something this important."
Illumi watched him without a word. Lying carelessly with his head in his lap, completely unguarded, Hisoka couldn't have made it easier. His words and his actions didn't seem to match. Illumi had met precious few targets who made themselves vulnerable to attack when they knew an assassin could be sent their way.
He'd never turned down a client before. He wasn't of the habit of asking questions. Why they wanted a target killed didn't matter. Ideally he shouldn't be questioning Hisoka, either.
"You can't afford me."
It was not the first time he had suggested this, but Illumi had never thought he was serious. It was the only retort he could come up with.
Surprisingly, Hisoka dropped the subject, returning an amused hum before pulling away, leaving him feeling strangely deprived. He stared unblinking as the magician turned around to go to sleep comfortably in his bed. Vulnerable, again, around Illumi.
You're the only one I can trust with something this important.
Well, he supposed he owed it to the magician to give him a death he deserved when the time came. He'd do right by him– and not just because of the obscene amount of money he would be paying by contracting him.
Because– they weren't friends, no, because he valued their working relationship, in lieu of all the help lended, and such.
Illumi slipped out of bed, heading for the shower. As far as he was concerned, his reconnaissance here at Heavens Arena was done.