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I.
In the midst of destruction, Sawada Tsunayoshi rises from the ash with a crown of fire blazing on his forehead and the heat of the sun melting in his eyes.
(In hindsight, Rokudo Mukuro never stood a chance. It was funny. Until it wasn't.)
"Good work, Tsuna," Reborn says, Rokudo Mukuro barely-conscious on the concrete crater he'd been beaten into. "You can rest now."
But Sawada Tsunayoshi does not respond. He doesn't even so much as twitch. Instead, he looms over Mukuro, inhuman orange eyes carving into the --manboychildsoulsixsixsix -- and there is a strange air about him. Too still. Too heavy.
A chill runs down the World's Greatest Hitman's spine when he catches sight of his student's eyes. Empty. There is nothing there. Just an endless void of sun and heat and fire, and Mukuro must see it too, because he does not even dare to breathe.
"Tsuna," Reborn says, and his tongue is too thick on his tongue. There is something racing in his veins, but some small part of him protests it to be fear. He is the World's Greatest Hitman, is he really afraid of a fourteen-year-old boy? And yet, and yet, and yet...
Tsuna reaches out for Mukuro, and the boy looks more terrified than he has the entire fight, too terrified of what should have been a fourteen-year-old child, but then Tsuna's body gives way, regardless of whatever he had been about to do, and he collapses to the side, unconscious and once again human.
Reborn, for the first time in over thirty years, cannot do much more than stare, his heart thundering in his chest and instincts blaring at him even as they calm. A tidal pressure he hadn't even realized had been building up in the room releases, and the world seems to get ten times lighter.
Mukuro pants for breath, glances one last time at the brunette fast asleep beside him, and then his body gives out too. Chains shoot out to take away the perpetrators. Reborn stays with his student until the medics come.
(It doesn't occur to him until much, much later that the Vindice had not appeared until Tsuna was asleep.)
II.
Training has been going well. Reborn has been monitoring the situation with extremely delicate care, searching and searching for any sign that Tsuna might slip into that strange trance-like state he'd entered in his first battle with Mukuro.
But no, his Dame-student is learning how to use Hyper Dying Will Mode properly, and doesn't show any signs of even remembering that anything odd had happened the first time. It both sets him at ease and sets him on edge. Because if Tsuna had no memory of it, then what the hell had that been? It was certainly no illusion, or hallucination.
But, well, there will be time for that later. For now, they have a battle to get through. Reborn watches from the sidelines as Tsuna freezes Xanxus, and his empty, cold black heart swells with what might be pride. Sawada Tsunayoshi will go so, so far.
And then Xanxus breaks free. And then Xanxus puts on the ring. And then Xanxus tells his men to kill all of Tsuna's Guardians upon failure to use the Vongola ring's power.
And then the shift occurs again.
His hairs rise and skin prickles when he sees that blank look slate onto Tsuna's face, and Colonello, who has experienced war and the life of an Arcobaleno, goes pale. Shamal is nearly as experienced as them, and stops breathing. The others are too young and too inexperienced to know to do much more than freeze in shock.
For a split second, Reborn almost pities Xanxus. Because Xanxus is Wrath and rage, a man who has lived on blood and murder, and right now his expression is that of someone who has stepped into the dragon's layer with nothing but a spoon to defend themself.
And then he curses in his head, because Tsuna's Guardians are faltering- staring at Tsuna like they've never seen him before. The Famiglia has only just truly come together to fight this major battle, but if their faith is shaken-
He can't think anymore because Tsuna is moving, and a Sky has never looked so terrifying in its all-encompassing glory before. His orange eyes are so bright that they're more other than human, and Mammon falls backward, body shuddering without permission.
The entire battlefield is holding its breath, watching, waiting, and unable to lift a finger under the immense pressure that has exploded from this tiny teenager's body. The crown of fire on Tsuna's head has never looked so fitting- because this is the pressure of a king, born and bred to rule.
But- this isn't Tsuna. This is too cold and unfeeling and apathetic to possibly be the foolishly naive brat who gets failing grades and runs away screaming at the sight of chihuahuas.
Not-Tsuna takes another step, and in what might be the most impressive display of loyalty Reborn has had the empathy to commend, Belphagor, in his young and wild recklessness, steps in front of his Boss with his entire body trembling.
"This is my king," Bel says, his voice shaking but there is something poetically beautiful about the way he holds himself. The blood of royalty is more apparent than ever in a situation like this.
Xanxus is staring at the boy -- he must have only seen Bel as a child before he was frozen -- like he's never seen him before. Reborn briefly wonders why Xanxus would even want to be Decimo when he's already practically king of a small Famiglia of elite assassins anyway, but then again, it's more about the principle of the matter.
Squalo twitches like he wants to roll himself out of there, wheelchair and all, and throw himself into the firing line too. He doesn't, because he's loyal not stupid, but his flames flare brightly in the air as if he were a Lightning meant to distract instead of a Rain meant to calm.
Not-Tsuna slowly tilts his head, and that one movement is more terrifying than it has any right to be. Bel chokes on the pressure, crumbling to his knees, and Xanxus jerks on the ground, but his body is too weak from the backlash to much more than twitch.
"DO nOT TouCh WHAt bElongS tO a KiNg."
Reborn bites down on his lip to prevent himself from screaming. Not-Tsuna hasn't even moved his mouth, but the weight of his voice feels like it's imploding his brain, making it vibrate beyond anything it's supposed to be able to handle, and he so clearly sees death flash before him-
And then it's gone, and Tsuna is back, staggering to the ground on one knee. He looks confused for a brief moment at their expressions before he falls to the side, unconscious again.
And then suddenly, everyone remembers how to move. Gokudera catches Tsuna's body, Yamamoto comes to the left to support them, and some Varia goon comes to report that their forces have been destroyed by Lancia.
Not that it matters. Looking at the Varia now, Reborn can say with absolute certainty that no one besides a suicidal freak without any sort of instinct would try to rise up against the Decimo-to-be among the witnesses here.
He lets out a breath and refuses to acknowledge the way it shudders, just the slightest bit. Tsuna is going to be the death of him, for so, so many reasons. Yet, not even that knowledge can drown out the morbidly curious need to know.
Curiosity killed the cat. (But satisfaction brought it back)
III.
Reborn has been dreading this the entire time they've been in the Future.
It was bound to happen sooner or later. Tsuna has been in and out of Hyper Dying Will Mode, and has been put under immense stress. Reborn thinks he might get grey hairs from the tension in the back of his mind, infant body be damned.
The Tenth Generation was able to more or less brush the incident off. Reborn explained it off as a condition of Primo's bloodline, as a wielder of the Vongola Sky Ring, but he knows and the other Arcobaleno and Mukuro and the Varia know that's not it.
So when Yuni sacrifices herself -- young, so young, he only ever got to hear her call him uncle a handful of times, too few times, why must fate be so cruel to the Sky Arcobaleno- no, the Giglio Nero? -- and Byakuran laughs, Reborn knows it's coming even before Tsuna's eyes dampen.
The pressure in the area digs down on them tenfold, and though Reborn knows what to expect now, bearing it is no easier than the other times. Xanxus and the Varia, a ways away from them, immediately back away, and Bel, ten years older and wiser and bloodier, smiles in an uneasy, nervous way.
Kikyo, captured and held on the ground, chokes and stares at Tsuna in the way he once stared at Byakuran- like one witnessing the crowning of a god.
And Byakuran-
Byakuran pales, his face draining of all color. Reborn doesn't even want to know what that means for someone who can supposedly see across parallel worlds. The Millefiore Sky's flames stutter, proof of how shaken he is, and then he licks his lips and says, "Oh. It was...game over from the start, wasn't it? Haha...just not...my luck."
Not-Tsuna raises his hand, his face smooth of emotion and anything human and hauntingly beautiful in its blankness, and Byakuran closes his eyes like a criminal come to accept the glave as pure bright flames explode in an instant and consume him- and scorching down the entire half of the forest.
One blink and the next is literally all it takes. Incinerated to dust. Reborn's chest constricts when Not-Tsuna then turns to face them, and he knows he's not the only one.
A part of Reborn looks up in panic. Unlike every other fight, Tsuna hasn't been damaged enough physically to immediately fall unconscious after. Which means...
Not-Tsuna's eyes sweep over them and then flick upward, as if they were no more than mere ants. When his gaze falls on the blue sky above them, something passes over his face, so faint that Reborn is half-sure he imagined it.
"It is not time," Not-Tsuna says, and this time, his voice is not the inhuman abomination it was before. It's Tsuna's voice, and yet also...not.
Multiple people hold their breath and Not-Tsuna closes his eyes, willingly surrendering his control of Tsuna's body. Surprisingly, Mukuro is the first one to move to catch him, looking calmer than most of the others can claim.
"In the ten years that passes," Reborn asks later, when the kids are out of range and it is just the two of them, monster to monster, "what happens to it?"
"We don't know," Mukuro admits, and he looks like a rat crawled up in his throat and died just by the admission. "One day, Tsunayoshi became furious, and it just never appeared. I don't think your future self ever told him about that other form of his. I had my theories, but perhaps it realized that certain things needed to happen in this timeline, without its influence."
"I see," Reborn says. And he does. He sees everything Mukuro is saying, and everything he isn't.
"Still, it is the man inside of him that I respect," the Mist says after a beat of silence. "The monster grabbed my attention, but Tsunayoshi worked on his own to keep it. Which is why that idiotic man will get a very unpleasant welcome back from me, kufufufu..."
Reborn tugs his fedora down and watches the man go. Mukuro grows up to be a fine ally, which is one thing to worry slightly less about.
That only leaves Reborn with about a hundred thousand more.
IV.
If the universe could just not poke Reborn's student with a metaphorical stick, then that would be very welcome, thank you very much.
It's obvious that Daemon Spade is completely off his rocker. If he weren't, then he would've known from his extensive investigation of the Tenth Generation that pissing off Tsuna was not the way to win the war. Touching his friends? That was a guaranteed way to wake the beast. Byakuran could attest to that.
He's actually really proud of Tsuna, beyond what he can say. It's all Tsuna that hits Daemon with the XX Burner, pulling off a beautiful finishing move that leaves even him impressed. It would have been the perfect happily ever after if Daemon had just done his damn job and died.
Mukuro actually seems a little worried. That is, after all, his body, for all that Daemon is wearing it like a piece of clothing. Reborn sets the owl upright just as Daemon shatters Tsuna's bones, and tries not to feel as not-worried as he is. Because he's not worried. Well, scratch that- he's not worried about Tsuna. More like, he's worried about everything else besides his student.
Not-Tsuna emerges just as Enma sends over the Shimon ring, and the being allows the rings to combine, though it's a completely unnecessary move as it moves to block Daemon's punches without even batting an eye at the fact that Tsuna's bones should be completely shattered. Can it not feel pain?
"Annoying." And with that verdict, Not-Tsuna raises his hand in a gesture not unlike how he had positioned himself against Byakuran.
Chrome, the ever-loyal follower, shouts, "B-Boss! Please, don't! T-That's Mukuro-sama's body!"
Not-Tsuna actually listens to her cry, shifts position, and pushes Daemon lightly on the chest instead. He still goes flying back as if he'd been hit with a literal train instead, but that sort of damage can be fixed with flames, because they're the magical mafia and what can't be done with the power of science and determination and...killing intent?
Reborn glances down at Mukurowl. This brat better be damn grateful to that girl, because she probably just saved him from the unique experience of watching his own hijacked body getting vaporized right in front of him.
"Why do you weep?" Not-Tsuna asks as he walks forward, and everything about him is so light he might as well be floating instead. Enma is confused, terrified, and probably more than a little worshipful, if the look in his eyes is anything to go by. Also, he's completely high on adrenaline which means the terror hasn't sunk in yet.
Chrome blinks her tears away when Not-Tsuna comes to a stop in front of her, and Mukurowl's wings flutter restlessly in Reborn's arms. The hitman smacks the owl, mainly to prevent him from doing something stupid like rush out there. Reborn eyes Not-Tsuna. It's still as inhuman and apathetic as ever, but he can see a hint of something, and that's more than the complete and utter blankness from before.
"H-He hurt everyone," Chrome whispers, a tear falling from her eye. "A-And he got Mukuro-sama's body hurt so badly. Please. I just- want everyone to be safe."
Damn. Damn. Reborn really needs to re-evaluate his impression of Chrome, because there is no way in hell that the girl didn't just choose her words very carefully. Mukuro is all but radiating smug, pleasantly surprised pride, though Reborn doubts he can take much credit for this. This is all Chrome.
Not-Tsuna reaches out and wipes away her tear, watching it in the way one would observe the passing of the days. It evaporates moments later, and he strides past her and toward Daemon, who has been pressed down by an unseen force Reborn is going to assume if Enma's gravity for the sake of his sanity (ignoring the fact that there aren't any trademark gravitational rings from the Flames of Earth and- no, stop, don't go there.)
Daemon struggles, but it's a fruitless endeavor. Not-Tsuna douses out his flames, observes him somewhat blandly, and then thrusts his hand into the man's chest. Mukuro winces, Chrome whimpers a little, and Reborn tries to resist making a similar reaction when Not-Tsuna yanks -- something -- out from Mukuro's body.
It takes him a moment to realize that Mukuro's body isn't bleeding, and there's no wound. Not-Tsuna is currently holding something pale, almost translucent, and writhing like someone set it on fire. Looking closer, it seems to be...Daemon's spirit?
"As all things should," Not-Tsuna says, adjusting his hand and then wrenching. "Return to the origin."
Daemon disappears. Just like that. At this point, Reborn is kind of wondering whether he should take a gamble like Chrome and just straight-up ask Not-Tsuna to cure his curse, because obviously, there is some freaky shit going on here and since he's not going to be able to stay away, he might as well join in.
Mukuro's spirit returns to his body, judging from the way Mukurowl slumps slightly, though the teenager very wisely does not open his eyes and dance about in glee at escaping jail. Not-Tsuna is still there, after all, and he seems reluctant to disappear this time. Which. That can't be good.
"Undead dare to roam the realm of the living?" Not-Tsuna asks softly, and oh. Oh. It's very clear who -- what -- he's talking about.
The Vindice very pointedly does not come out. Reborn wonders if he should be feeling as vindictively gleeful as he is right now, but really, the bastard had it coming. Dropping cryptic hints about the infantile Vindice with the clear pacifier and then dangling the answers away from him as if he were another puppet in a show- well, this is just karma.
Not-Tsuna seems to contemplate forcing Tsuna's body a little more but then decides against it. That also has connotations Reborn needs to think about. Why does Not-Tsuna care if Tsuna's body is damaged or not? The obvious answer would be because it's Not-Tsuna's body too, but that means that Not-Tsuna is literally living inside of Tsuna's head, albeit dormant, and that isn't very good either.
"Soon," Not-Tsuna murmurs, sitting down. "But not yet."
Tsuna falls forward. Reborn fingers his pacifier. So many unanswered questions. It's too bad his Dame-student knows so little about this situation it's not even funny.
Mukuro opens his eyes, checks the clearing is safe, and then goes on a tangent about how he's now free and stuff. It's really only half-effective because there's no one else around to listen. Reborn glances over. It takes a few seconds, but then finally, the others are released from their card-prisons. A time-delay effect? Or maybe that's how long it took for Daemon's spirit to pass into the afterlife.
Either way, Reborn is ready to call it a day.
V.
"In this case," Checkerface says, distant and amused, cold and condescending, "I think it's good manners to refuse."
Reborn watches with something like hope as Not-Tsuna emerges to the front of his student's conscious, the air around him falling still instead of charged, in the tell-tale signs of predator's aura. Mukuro starts to laugh on the ground, a little hysterically because he's also half-dead from blood loss, and everyone who was standing on the sidelines now rushes to get the injured out of the battlefield.
Tsuna defeated Bermuda, all on his own power. Not-Tsuna? Not-Tsuna's opponent is right here, standing there in all his checkered, assholish glory.
Not-Tsuna's eyes flutter open, those bright, bright orbs that are more and more enchanting every time Reborn sees them, and his flames swirl around him almost...gently. This is nothing like the beast of detached observation that first emerged. Is that, Reborn wonders, Tsuna's influence? Changing even his own unconscious other half to something gentler?
Waves of warmth trickle around the clearing, like streams of sunlight during spring. There is still a sliver of fear in Reborn's heart, because Not-Tsuna is so other that he naturally provokes such emotions, but there is a distinct lack of terror. It's as if Not-Tsuna has gentled his -- its? his? Reborn still has no idea -- majesty; blunted it so they can withstand his presence more comfortably.
Checkerface's staff drizzles away into nothingness, and the man removes his mask, revealing the face of Kawahira, who they met in the future. Reborn memorizes every inch of that face -- even though he sincerely doubts it's the man's actual appearance for all that it seems such -- just in case.
"Your name, illium?" Not-Tsuna asks, wind swaying gently through his bangs. Illium. Reborn hasn't heard that term before.
"Kawahira," Checkerface says, his voice soft, muted, humble- nothing like he was mere seconds ago. "My name is Kawahira."
Not-Tsuna moves forward, and the warmth radiating from his body follows. Byakuran, also half dead like the others -- though Reborn really wouldn't mind if this one just, you know, croaked -- cranes his neck to watch, looking similarly humbled. There is a curious lack of fear on his face, for someone facing the being that killed him in one future.
"Kawahira," Not-Tsuna echoes, and there's a shift in the air, the crisp sound of chimes tinkling somewhere far, far away. Checkerface -- Kawahira -- lowers himself as Not-Tsuna reaches out, hand brushing against his cheek. It is intimate from afar and surgically precise any closer.
"I thought..." Kawahira starts, then stops. He swallows. "I believed the gods to be dead."
God. Gods. Reborn's brain starts, stops, then forcibly starts again. Behind him, Skull makes a dying fish sound. He doesn't even want to know what Verde's face looks like right now- actually wait, he kind of does. He side-eyes the Lightning, and gets an eyeful of Verde's constipated, reboot-reboot-reboot expression.
Not-Tsuna lowers his head to whisper something in Kawahira's ear, and something like a smile curls onto his face as Kawahira physically staggers, face pale. Reborn freezes in place, a chill running down his spine. That, he realizes, is the smile of a god. Beautiful in its cruelty, glorious in its apathy, relentless in its power.
"We return to the beginning," Not-Tsuna says, turning away, and it's not quite clear who he's talking to- them or Kawahira, or both, or neither. He walks toward Talbot, who bows gracefully, and touches the containers in his arms.
His gaze briefly passes over Yuni, who curtsies with lightly shaking hands. She's brave, incredibly so, and Reborn might be imagining it but Not-Tsuna's gaze seems to briefly, just barely, linger on her before moving on.
The containers float into a circle around Not-Tsuna, and the pacifiers around the Arcobaleno snap off their necks to obey his call. Reborn stares numbly as the weight he's held for decades so easily leaves his neck without so much as stinging him.
Not-Tsuna raises a finger, and the containers flicker with balls of white fire, flickers of black around the edges. It is a pure, condensed flame of a power Reborn doesn't even know how to label. The flame of a god. He kind of wants to laugh, but this isn't really the best time to be breaking down into hysterics.
The pacifiers slip into the containers, passing through the glass surrounding it as if it were made of water, and turn grey as soon as they touch the fire, shattering and then turning into crystals. Metal. Their original form, Reborn realizes.
Not-Tsuna flicks his hand and the containers float back to Talbot and Yuni, who immediately catch them, both careful and quiet, instinctively wanting to avoid catching the attention of the being before them. Then he turns to Bermuda, on the ground, and the leader of the Vindice stiffens.
"Abomination," Not-Tsuna seems so far from interested in the undead that it's almost laughable. As if he were merely a bug, or a speck of dirt. "You corrupt the lines of life and death."
Bermuda tenses, and then shouts, "Should I have died instead then, to Checkerface's whims?! I scraped my way from death with my own determination-!!!"
"Silence," Not-Tsuna's pressure turns from gentle to suffocating in an instant. Several people actually fall to their knees, choking, and Reborn just barely manages to keep his footing. "I did not allow you to speak."
Damn. Damn. Reborn's eyes flicker from Bermuda to Not-Tsuna, then back to Kawahira. Between the three of them, it's obvious who the true danger is, and that thought makes his throat itch for a drink. God. Gods? Ugh. This is really not the way he wanted to unravel the mysteries of the universe.
"I am Judgment," Not-Tsuna says softly, raising his hand in Bermuda's direction. "And you are the Judged. That is what it means to be [****]."
And there's a flash of blinding light. Reborn closes his eyes, shielding his face. This is a much brighter light than the one that killed Byakuran in the future. He's not even sure if its fire, or just plain light.
When he blinks his stinging eyes open, Bermuda is still on the ground, breathing, and looking stunned. Reborn feels stunned too, because not only has Bermuda's pacifier been molded into a gem of pure black -- not unlike his old pacifier -- he is also human, despite the Boss Watch having passed the allotted time. A quick glance shows that Jaeger is also donning human flesh and skin, face slack.
"Outside the Balance, new lines are drawn," Not-Tsuna turns and walks away as if nothing significant just happened. "Be thankful that this child finds you precious."
Bermuda couldn't look any more shocked. 'This child'...that's definitely referencing Tsuna. Reborn tugs his fedora down, relying on the familiarity of the motion to calm his buzzing nerves. Looks like his Dame-student's soft heart has saved yet another group of dirty criminals. Him included.
"Wait," Reborn calls, sensing the moment when it seems like Not-Tsuna is about to retreat into Tsuna's body again. "What are you to Tsuna?"
Not-Tsuna turns, and the full force of the being's gaze on him is even more intense than he thought it'd be. Still, he holds his ground.
"...what do you think?" Not-Tsuna smiles, but this time, it's soft and quiet. It looks like Tsuna.
Oh. Oh.
The being seems to know when Reborn understands, because he closes his eyes again and slumps to the ground.
And just like that, dawn breaks.