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Mukuro knows rebirth better than anyone.
Six Paths of Reincarnation wasn’t just a flashy title; he had died and come back six times over, stronger for it but feeling a little less human every time. He didn’t even think he could die again.
“Boss, it’s gross.”
Unfortunately, he was not correct.
“He’s my son, Kai,” The older man holding him says. Holding him . Because Mukuro is currently nothing more than a wiggly, weak one year old. The bloodlust he feels is immeasurable. “That means he’s practically your little brother.”
“You’re too old to have more kids,” The boy, Kai, says brashly. He’s looking at Mukuro like he’s a particularly gross maggot. Mukuro tries to return the glare, hoping he’ll send the scum to hell.
(Unfortunately, the First Path does not swallow the brat in searing flame and the screams of the damned.)
Mukuro internally cringes at how his… father laughs, somehow not offended, “I know, I thought the same, but he still happened. Here,” He offers Mukuro to Kai, “Just hold him Kai. He’ll be your subordinate one day, try to instill some loyalty while he’s young.”
Ugh. The old fashioned clothing and the layout of this building had triggered Mukuro’s suspicions, but now he knows for sure. Yakuza , of course he has to be reborn into this world’s seedy underbelly. Mukuro still finds himself smiling, unable to form a real smirk; since his Boss isn’t here… Well, there’s no one around to tell him no to torturing criminals.
Kai crinkles his nose. But Mukuro soon finds himself in the young man’s arms, definitely not being held correctly. The boss corrects Kai’s baby holding technique gently. Then Kai’s gaze drifts downwards, so Mukuro just stares up at him, unblinking, thinking of the most creative threats he can imagine. (He’s a Mist, so there’s no real limit to them.) Might as well creep the kid out as his first mode of attack.
“Why is he just staring?”
The boss laughs, unaware of his infant’s inner mantra of I will make my first finger painting with your blood , “Babies like bright colors, he might just like your eyes!”
Mukuro continues staring. Kai looks greatly uncomfortable. Good.
“I don’t need a brat for a subordinate,” He finally says after some barely noticeable fidgeting, “I’m seventeen, he’s one. That’s too big of a gap for him to be of any use to me.”
For the first time, Mukuro sees the boss look more stern than jovial. “Kai. I want you to try to form a relationship with Hisao. I know that you think he is nothing more than a baby, but he is my son. I promise you that he will help guide you on the right path in the future.”
The only path Mukuro is guiding this kid towards is the path straight to hell. He wiggles as violently as his small body will allow, almost making Kai drop him. So the boss takes him back and smiles when the wiggling stops. It's not that Mukuro wants to be held-- he certainly did not, especially not by a yakuza boss, but he would rather not fall to the cold ground below. He pouts as he is cradled and listens as the old man begins to talk about something new, drifting off with thoughts of escape already formulating.
Mukuro grows up so slowly it's painful. Having to relearn every simple function of his body is agonizingly, mind numbingly boring. Most of his time is spent with his “parents'' in what almost looks like a normal home, but his “father” often brought him to his office to get him used to it. While this wouldn’t bother a normal infant, Mukuro loathes it, and makes his displeasure known.
His screaming rage does not get the desired effect.
“You must need a nap,” Is always the response. Condescending words mixed with a fond smile. Then he’d be offered some new, noisy infant’s toy. Such humiliations had to cease immediately .
Spite is what fuels him to advance himself beyond the limits of his age group. He skips spoons and forks, going directly to training chopsticks. Practices his coordination to be at the level of a 2 year old, eventually able to walk and run. Leaves behind diapers as soon as possible.
By the time he’s three his physical prowess is more on par with a six year old’s. Not quite the gap he’d prefer, he’d rather have his full adult self back even if he had to stay in the form of a child, but it was also less suspicious this way. Physical milestones were at least easier to reach than language-related ones, his progress hindered by the roadblock of a child’s uncoordinated tongue.
His growth rate has earned him annoying amounts of praise from his aging parents. Everything he does is met with a so smart! Or a wow, good job! Mukuro endures enough babytalk in a single day to make an actual infant weep. Dumbing himself down a bit around them was necessary. It was better to stick with simple phrases pronounced adorably wrong, rather than showing them his latest mastery of diction and grammar. Besides the doting, he also wouldn’t push his luck with how far our son must be a genius! could go.
Kai Chisaki, on the other hand, was free range.
The Shie Hassaikai boss left Mukuro with his “older brother” ( ugh ) more often, alone, fully confident that Kai would ensure his young son’s safety despite the man’s obvious dislike for “Hisao.” Kai would complain, but always gave in to his boss’ requests.
Babysitting was apparently more like dog sitting, to Kai. Have the kid near enough to him to hear if there was some kind of emergency and only check in with his eyes occasionally. This gave Mukuro some freedom. Not enough, but some.
“I want to read something else,” Mukuro says, scowling.
Kai looks away from the documents spread across his desk, glaring, “Boss said that’s your favorite book,” He grits out, “Are all three year olds so picky?”
“It’s not. I lied. Give me the book on your desk.”
“ Quirked Genetics Theory ? You don’t even know what genetics is. Leave me alone and read your book, I’m busy.”
“Better than Momotaro. Give it to me.”
Mukuro wishes he could mock Kai for how much restraint it must take him not to throw the heavy volume at Mukuro. Unfortunately, he’s not supposed to know the word ‘restraint’ quite yet. He takes the book and brings it back to his usual spot on the office’s carpet, ignoring Kai’s hissed “now leave me alone.”
Even if he’s not being watched, Mukuro still acts confused as he squints at the dense text. The illusion is only helped by the fact he doesn’t know what Quirks are, really. He’s heard his parents mention quirks to their first child, his older sister, over the phone. In relation to the possibility of a future grandchild of some kind. But that was it. He rarely got out of the house either, with his mother ill and his father either entirely focused on her or his yakuza work. Kai was, supposedly, meant to take him out for sunshine and fresh air, but he never did.
“What are Quirks?” Mukuro finally asks, pretending to be interested in a diagram of a human body with a few extra organs. Recessive fuel sac? Combustion valve?
“I told you to stop annoying me,” He says, but there’s only a slight pause before he says, “Quirks are a disease. Almost the entire human population is affected. A horrible, stubborn malady. You’re around the age where you’ll contract it as well.”
“Do you have a quirk?”
Kai raises an eyebrow, still annoyed, but seemingly intrigued, “Are you always this chatty?” And then he grabs the children’s book Mukuro left on the ground beside him. Instantly, it disassembles, then constructs itself into a 3D replica of the Shie Hassaikai's crest as quickly as had ripped apart, “I unfortunately did not escape the disease’s spread. Its name is Overhaul.”
Interesting. It was a bit like Flames, abilities calling to mind Storm and Sun, but the flames were absent. Almost the entire human population could wield impossible abilities like this? That had to be difficult to control. Flame users were kept in check by the Mafia, kept in neat little rows because, while many people had Flames, it was still a controllable amount if you knew how to use the masses’ fears and darkest desires to your advantage.
“When will I get my Quirk?” Mukuro asks. He would prefer his Six Paths of Reincarnation back, he’d gone through hell on Earth to gain his power and would prefer not to lose it, but it would be… interesting, to gain a Quirk. Beneficial too, if it was powerful like Overhaul was.
Kai rolls his eyes and clicks his tongue, “You shouldn’t desire to be diseased, enjoy the purity granted by youth. You’re three, so you should be infected by next year. Though, the Boss and his wife are Quirkless, so…”
Ah. Infuriating.
Mukuro looks back down at the book, uninterested in keeping up his facade of a confused toddler when met with knowledge about a fascinating concept. For as annoying as the man is, Kai has given him lots to learn about.
Quirks are fascinating, but they also give him unpleasant memories of Estraneo’s human experimentation. Ken’s channels could easily be considered a mutant quirk. These memories lead him down an equally unpleasant train of thought. There could be children out there being made into weapons, but instead of being tortured to gain powers, their DNA made them destined for such a life. He tries to wave the thought away, but it stays lodged in his mind like a thorn stuck in the bottom of his shoe.
He has his own Quirk to think about. Mukuro’s fourth birthday passes without so much as a twinge of power. His fifth, much the same. He’s six years old and has shown no sign of developing a quirk when his father finally brings him to a doctor.
“See this, Hisao-kun,” The doctor says, speaking gently, “This is an extra toe joint.”
A red circle in his X-ray marks where the joint is. Mukuro boredly wonders when this is going to be over. He just needs a yes or no answer, the dreary atmosphere of the underground doctor's office makes his skin prickle.
“So?” Mukuro asks, eyebrow raised, “I don’t think that’s a Quirk.”
Now it’s his father’s turn to speak gently, like Mukuro was currently rolling on the ground and having a fit instead of sitting down calmly, “Hisao. When someone has two toe joints, that means they won’t get a Quirk. It means that you’re… Quirkless.”
The doctor winces, shifting uncomfortably and looking at his father. Like she fully expects a tantrum in the middle of her examination room. She probably does. Most kids would be upset.
“I see. That’s inconvenient.”
They leave the doctor’s office with so much as a whimper. Instead of going straight home, his father has the driver take them to a bakery. Mukuro is treated to an entire small chocolate cake to eat by himself while his father frantically talks to someone over the phone. Apparently, this is a heart-breaking outcome, but Mukuro’s mind is solely on Six Paths of Reincarnation.
Since he came back in a new universe, is there a way to regain his previous power? Dying six times over would be inconvenient. Maybe his body would remember it after a single death. There were lasting imprints of those previous lives still etched into his soul, he felt the ache of them…
“It’s okay to be upset,” His father says, suddenly, finally pried from his phone, “That you don’t have a Quirk.”
“Well, I’m not upset,” Mukuro replies with a shrug, taking another bite of cake. It’s really good. Maybe he should force Kai to take him outside sometimes, if only for cake, “I don’t really care.”
He’s given a look that has an annoying amount of pity behind it, “Well. If it ever does upset you, just tell me. We can… Talk about it.” His father says, before his phone buzzes. The older man curses under his breath, apologizes, and walks away to take his call.
There’s a bitter part of Mukuro that wonders how he’d feel about that, if he were a normal child.
After Mukuro finishes as much of his cake as he physically can, they drive back to the Yakuza compound in silence. The energy when they enter is nervous. Kai greets them at the door.
“You’re Quirkless, Hisao?” He asks, a suspicious gleam in his eyes.
Mukuro nods, despite the fact his father is giving Kai a disapproving stare. If that wasn’t enough to make Kai run off like a kicked dog, tail between his legs, then Mukuro being Quirkless was more important than the boss’ approval.
Instead of any verbal reply, Kai nods, almost seeming proud . After that, the change in his behavior is noticeable. He talks to Mukuro more. Talks about Quirks especially .
Specifically, his desire to eliminate them entirely.
Kai seems to have formulated this grand destiny for himself. He’ll be the one to rid the world of this plague they are suffering with. When he does this, the Yakuza will rise above Heroes and Villains once again. The Shie Hassaikai would regain their former glory. All of this in service to his beloved father figure, instead of just the egotistical ramblings of a man who could do with a few good jabs with a trident.
It takes a moment to realize why this is making him so annoyed. But then he realizes. This was just his younger self’s crusade against the Mafia again. It’s just different packaging. Hatred and childhood influences bottled up and left to fester, resulting in a complete extermination of something. Would there be a Tsuna to steer Kai from that path? Did Mukuro really care? Kai was a presence in his life, but not one he cared about. Mukuro was using him until he was old enough to go out on his own.
Well, it wasn’t like that dream of Kai’s would get anywhere.
Mukuro is eight when his father brings a young, white-haired girl to the compound. He had started living there permanently, in a guest room, after the sudden death of his mother. Even in this new life, he didn’t care much for his new family, so he hadn’t found it in himself to grieve for her. Unlike his father, who still lived in the old, empty house she’d passed in. Kai had taken on much of the actual work of a Yakuza boss to let him take his time mourning, any visits the actual boss made to the compound were rare.
“This is Eri,” The old man says, smiling tiredly. Grief weighs on his aging body. “She’s quite a bit younger than you, Hisao. She’s three years old. Please, treat her like your little sister.”
Eri fiddles with her hands, “H… Hello.”
“Hello, Eri-chan,” Mukuro says, giving her a smile, “My name is Hisao. It’s nice to meet you.”
Is this an adopted child? No, Eri has the same face shape as Hisao. And while her hair was white and her eyes were red, it was probably from albinism. Then who was she? There was no way his father would have another biological child.
“Where did she come from?” Kai asks. Ah, Mukuro forgot he was there.
A heavy sigh, “She’s my granddaughter, my daughter’s child. She recently developed her Quirk… And discovered it by making my son-in-law vanish. I was hoping you’d be able to properly identify her Quirk.”
Mukuro frowns. His sister abandoned her daughter?
“You’re so good with Hisao, I felt like I could trust her with you. And… aren’t your quirks similar?”
Kai looks at Eri. Eri buries her head into Mukuro’s stomach, peeking out at Kai after a moment’s worth of hesitation. It’s clear that Kai didn’t like an “infected” child close to the one Quirkless person in his life, but he nodded; “Alright. Leave her to me.”
“Hisao-oniisan,” Eri whispers, after the older men have gone to another room to discuss the details, “Is… Kai-san nice?”
Was Kai nice? Not to the Quirked, certainly. Or much of anyone. He could be pleasant to Mukuro, and a few others. But those were rare instances.
“I don’t know. But if he’s ever unkind to you, let me know, okay?” Mukuro says instead, ruffling her white hair.
She nods.
Even if he spent a lot of time with Kai, Mukuro still didn’t find him a pleasant person. He was a tool for Mukuro’s own means. A Yakuza with something sinister lurking deep within his core that he couldn’t trust Eri to be around. Even if Mukuro was still a small child, physically, he had been sure to keep a routine that gave him a bit of physical strength. If push came to shove, Mukuro could find a way to dispose of Kai and leave with Eri in tow.
They don’t see the older men the entire rest of the day. Mukuro takes it upon himself to get her fed, her teeth brushed, and tucked into bed beside him. While he didn’t consider himself charitable , he figured that children were worthy of this sort of care. They were innocent until made guilty, after all.
Besides, Mukuro had forgotten how much he liked to have someone relying on him like this. It made him a bit nostalgic. Ken, Chikusa, and dear Chrome had to be somewhere . He could feel Chrome’s presence, at the very least, in the very depths of his core.
It’s been so very long since he’s felt this… prote- possessiveness. Over the people who he had claimed as his a lifetime ago. When he left this place, he would find them.
But, with Eri’s arrival, it seemed like his departure would be delayed a few more years.
Most of Mukuro’s time was taken up with Eri after her arrival. When Kai wasn’t running tests to see what her Quirk was, she would spend all her time in his room. A toddler bed had been moved in, along with a few small toys Mukuro remembered from his own time as an infant in the compound. Her small clothes hung beside his own in the closet.
He wasn’t a fan of games, but he played with her when she requested it. Make believe was her favorite, little hero stories acted out by the two of them, with the help of a ratty doll she was fiercely attached to. Sometimes he snuck her out to go look at the outside world. At the end of the day, he was the one tucking her in.
It wasn’t a stretch to say he’d grown a bit attached.
Which is why Kai’s suggestion infuriates him.
Technically, Mukuro wasn’t supposed to overhear. Discussions of Eri’s Quirk were adult business. But he had quietly followed Kai and his father to the meeting room, pressing his ear against the door to listen to Kai’s discoveries.
Rewind. A Quirk that gave Eri the ability to reverse a living being's body back to a previous state. She hadn’t just blipped her father out of perceivable reality; she had rewound his existence back to complete nothingness. It was unlike any of the few Quirks from their mostly-Quirkless family, a mutation that was as powerful as it was dangerous.
And Kai wanted to use that Quirk for his own goals.
“Don’t you understand what her Quirk could do for us!” Kai exclaims, something wild in his usually flat voice, “I just need to test its effects! Pops, this can bring the Shie Hassaki back to our formerly glory -- don’t you want that?”
“I don’t want my granddaughter used as a tool. She’s not Yakuza. Just like my daughter wasn’t.”
“Your daughter left her with us. Eri doesn’t need to be a part of the Yakuza. I just need your permission to run more tests--”
“No. Kai, you need to be reasonable--”
There was more arguing, but Mukuro had already left, walking back towards where Eri was. He had a sinking suspicion he knew how Kai intended to utilize Rewind. Somehow, he would find a way to turn Eri’s Quirk against others’ Quirks.
She would become his weapon, a cog in the machine that Kai would use to make his ideal future a reality.
Mukuro grabs a few things in a hurry; A pair of Eri’s shoes. An outfit and a blanket each. A few books and the doll Eri liked. Traveling light was essential, weighing themselves down as little as possible to reduce fatigue. They would find food and water elsewhere, there was no time to sneak into the kitchen. All that mattered right now was escaping before Kai decided to put his plan into motion.
He doesn’t wake Eri, because for such a young girl she sleeps like a rock. He coaxes the backpack onto her back and ties a blanket around her like a cape. Then he hoists her onto his own back.
Before they can do a thing, the locked door of their room rattles.
Cursing under his breath, Mukuro tucks Eri into their shared clothes basket after quickly dumping it out. Her red eyes slide open and she tilts her head, confused, while he surrounds her with the least dirty pieces of laundry, “Hisao-oniichan…?” She says sleepily, “Are we playing?”
“Not really. Eri, don’t come out, even if you hear someone calling for you. Even if it’s me. I want you to be a good girl and hide, okay? Be very, very still.”
When she nods, obedient as ever, he covers her with a blanket and then the rest of the laundry. The rattling has turned into banging by the time he’s finished. The knob disassembles before his eyes. He was lucky enough to get done with hiding her before Kai decided to stop not using his quirk out of courtesy.
“Hisao. Where is Eri?”
“You’re going to hurt her, aren’t you?” Mukuro says instead, holding himself high, “I heard you talking to my father about her. You want to use her to ‘cure’ everyone, right?”
“She won’t be hurt. I just need a few samples of her blood, it will be painless. As long as she cooperates. You should cooperate too, Hisao. I’m doing this for you. Tell me: where did you hide her?”
“This whole plan isn’t for me. It’s not for anyone beside yourself, Kai. And I know that it’s especially not for my father. You’ve tricked yourself into thinking he’ll be proud when you bring back the Yakuza, but if you go through with it he’ll be disappo--!”
He can’t react before a hand lands on his forehead- and then his body explodes.
Mukuro had grown used to pain in his past life. He had died, or almost died, in every way possible at the hands of Estraneo. It was early in his life in this world when he realized some of the pain tolerance carried over, but not everything. He could stand normal injuries, but probably wouldn’t be able to ignore the pain of a hand being cut off. Even if the full realm of his tolerance had carried over, the sensation of being disassembled is unlike any other death.
Every atom in his body is being pulled apart. His organs shred into tiny pieces, each one somehow still working and pulsing with agony. His vision goes dark as his eyes turn into vapor and the sensation of Kai’s leather glove against his skin lingers in the air his body dissolved into.
And, as quickly as it started, the pain stops.
Mukuro shivers on the floor, trying to process what he just experienced. Pain… He’s not experienced pain in quite some time. He curses his weakness, at the way he can’t seem to remember how to move his body. The light in the room is suddenly too bright-- he buries his head in the shag carpet, despite the fact that it’s damp with what might be blood or vomit. Someone is crying; for a moment he fears it might be him, but then he remembers that Eri probably heard all that. He’s pretty sure he was screaming.
Kai says something, but Mukuro’s ears still aren’t quite working.
He doesn’t know how long he stays prone on the floor. Maybe hours? All he knows is that, eventually, darkness settles in…
Someone is carrying him.
Mukuro makes no noise when he wakes up, focusing on keeping his body limp and his eyes shut. He’s being held in the air by some kind of quirk, weightless with no contact with another person. Whoever is carrying him makes no noise, but they’re certainly not Kai. One of his subordinates, then. Maybe just a lackey. Even if he can’t actually test and see, Mukuro feels like he’s gained a modicum of control over himself. His limbs no longer feel like they’ve stopped existing and his brain has shaken off any hindrances caused by the explosion of pain.
He hears a door open. He’s being lowered from the shoulder of whoever is carrying him. It’s soft-- not a bed, but a couch. Murmuring fills his ears, low voices discussing something .
A hand grabs his own-- a prick of a needle. Perhaps he’s not quite fully healed, unable to stop the rush of memories from Estraneo, nor the panic that ensues. Mukuro’s eyes snap open, grabbing the hand wrapped around his own and intent on twisting until he hears the crunch of a broken wrist.
Instead, he feels an impact to the back of his head--
X
Realization only dawns on him after the kid’s body has already collapsed to the floor, blood pooling out of the dent made by the butt of his gun. Panic made you do stupid things; especially if you were a Yakuza with an inclination towards violence to solve your problems. Unfortunately, this is probably the stupidest thing he has ever done, and he already knows he’s going to die when the boss finds out.
“What did you do that for?!” His partner hisses, cradling his broken wrist close to his chest and staring at the body.
Or-- Maybe not a body? He crouches, taking the kid’s limp hand and pressing his fingers to his wrist. When he doesn’t feel a flutter, he tries the neck. Fuck-- fuck! He was going to die in excruciating agony. Chisaki had explicitly said no harm was to come to Hisao.
“I fucked up,” He says into the stillness in the room. He rises to his feet, slowly, backing away.
They were only supposed to draw blood. A small vial of blood, easy peasy, while the kid was out cold. But… Something about the viciousness he saw in every twitch of the kid’s body, trying to fight against whatever a simple needle, reminded him more of a feral animal than a human.
And he killed him.
He killed the kid Chisaki had forbidden anyone to even touch .
“What do we do ?” His partner says.
“I don’t know. We can’t just hide the body.” Getting out of the compound was impossible without being seen. Even if they somehow managed it, the Boss knew they were the last ones to see Hisao. They’d have the blame pinned on them even if they didn’t do it. Fuck, fuck, fuck--
Wait.
He freezes. There’s an… unfamiliar sound. It’s soft after first, but the volume increases. Is that…?
Strange laughter fills the room. Because that’s what the sound is: laughter. Ku fu fu fu… Kufufufu… Chills run down his spine, his eyes meeting his partner’s. Panic is clear in his face, like looking into a mirror. No mirth. Not even a twitch of the lips. Neither of them are the ones laughing. But there’s no one else in the room. Except… Slowly, very slowly, they both turn towards the corpse. It’s twitching, on the ground. Convulsing.
Laughing.
An aura of purple surrounds the body. One arm reaches out, hand planted on the ground, pushing the body up. In his other hand, purple mist gathers and solidifies into what looks like a trident, larger than the kid is tall. The three prongs at the end are sharp . Meant to kill.
“I suppose I must thank you,” The voice emanates from the body, filled with cold rage. His head tilts up, blood covering the side. His eyes have changed. One is still the blue-gray the previous boss had, but the other is bright red, the normal pupil replaced with the kanji for one . He smiles, still laughing, and plants his trident on the floor, “Your stupidity has given me my power back.”
The ground cracks open; the molten air of hell, dense and humid, eats their screams and muffles all outside noise, until the only thing they can hear is that damn laughter.
Kufufufu…
“One survivor was found in the carnage left behind by the unknown assailant’s attack on the Shie Hassaikai’s base of operations. Kai Chisaki, the group’s newly instated boss, was found in a catatonic state in what appeared to be a medical room. Last we heard, he has been unable to talk about what happened He has since been taken into custody and has been assigned a councilor, so police and heroes can question him about the incident--”
“Hisao… I mean, Mukuro-oniichan, I don’t want to watch this. Can you change it?”
“Of course, Eri-chan.”
A bright, cheerful kid’s cartoon replaces the news on their hotel room’s television screen. Eri is immediately engrossed, her eyes - duller, now, from what she experienced in that horrible white room - seem to come alive as a talking cat, who seems to be the protagonist, talks about love and friendship saving the day.
While it was inconvenient that his other Paths were still behind whatever block reincarnation had put on his powers, he at least had his illusions now. They had been enough to save Eri, and they would make it easier to survive as two small children without a guardian.
It also gave him the freedom he needed to find the other Vongola. And more importantly, his fellow Kokuyo gang members.
Between that and caring for Eri, Mukuro had plenty of work to do.