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“Ichigo, wake up! Wake up!”
Ichigo blinks sleep from his eyes, his body moving on autopilot, throwing the sheets off and reaching for his shihakousho and captain's haori. Years of late night alarms and patrols have trained him to snap to attention at a moment's notice, Rukia's side of the bed is already cool, so she's been up for a while. The matter must be really serious, if she's only coming to wake him now. Ichigo's brain whirs with possibility. A vasto lorde level threat that managed to slip past Grimmjow and Nel in Hueco Mundo, or a rogue Quincy cell with powers they haven't encountered before yet? They're still clearing out the dregs of Yhwach's forces all these years later.
He's just about to strap his sword to his back and leap out into the night to face whatever awaits them when Rukia bursts into the bedroom, still dressed in the old Chappy pyjamas he will never admit that he likes but secretly still thinks is the sexiest thing ever on her.
“What is it?” he demands. Now he’s awake enough to assess the situation and judge Rukia’s tone, there clearly isn’t anything actually wrong. Now he’s just annoyed that she woke him up in the first place, so this better be good.
Rukia’s eyes are filled with stars. “Nii-san has laid an egg!”
*
After he confirms that Rukia hasn’t been hit by some kind of mind-altering kido, and after listening to her babble on about them becoming an aunt or uncle, Ichigo gives up on the thought of getting any sleep that night and turns his attention to the crux of the problem: a fucking egg? Laid personally by Byakuya himself? Well, no wonder he always acts like he has a stick up his ass, he actually did have something up there —
Ichigo’s thoughts are interrupted by Rukia smacking him lightly on the shoulder, as if she can read his mind. He schools his face into a picture of neutral concern.
“I need to order lots of baby clothes from the Human World. Now. Immediately!” Rukia says. “Also there’s going to be a long list of people who want to babysit, but luckily we get precedence thanks to blood ties and I am just going to assassinate anyone who gets in my way—”
The penny finally drops for him, and Ichigo has to stop her there, waving his hands for her to rewind, rewind, rewind. Because what the fuck do you mean Byakuya laid an egg?
After a brief interlude of Ichigo, how the fuck do you not know about this already? and Well excuse me for being brought into this world by a tiny woman who gave me absolutely no say in it, it’s not like I had the time to figure out shinigami anatomy and reproduction while simultaneously trying to save your ass!, they both finally calm down enough to discuss the matter like adults.
“Look,” Rukia says, scrabbling around for her crayons, presumably so she can draw some incomprehensible diagram that Ichigo will not understand head nor tail of. “You at least know there are Five Noble Houses — Kuchiki, Shihoin, Shiba, Tsunayashiro and… another one I can’t remember the name of because they basically never do anything and are practically extinct.”
Ichigo nods. Yeah, he hasn’t bothered to ever find out what the name of that final house is been either.
“These five houses have existed before the creation of Soul Society itself, and they were never human to being with. Their lineage is one of pure spirit and the essence of life — and are somewhat related to the Soul King. Now, obviously the historical records are a little difficult to figure out here, but we believe that there must have been a marriage or union of the earliest Noble House spirits with the earliest human souls, and over time their descendants took a more human form,” Rukia continues, drawing an amorphous black humanoid figure and a more normal human with clothing.
He has to suppress a shudder at the thought of fucking something that looked even remotely like the Soul King, those early humans must have been pretty brave to climb something like that, but then again, he’s not surprised, it must be someone’s kink somewhere.
“So although they retain extremely humanoid features, there is one quirk that has been passed down across generations, which is —”
“Reproduction,” Ichigo muses thoughtfully, stroking Rukia’s hair. She’s come to nestle on him and is currently using his lap to prop up her sketchbook.
“Exactly. It also varies depending on the purity of the bloodline for each clan. The Shiba clan has mixed so thoroughly with human spirits that they’re able to mostly give birth the human way. The Shihoin clan’s ways are a heavily guarded secret for some reason, but I’ve heard rumours that they give birth… the wrong way round. As in, the baby comes out of their mouth,” Rukia pauses to shudder. “Because they’ve kept their lineage extremely pure over the last thousand years or so, they’ve retained the stranger parts of their reproductive habits. So for the Kuchiki clan in particular, it’s eggs. A mating season comes around in their life roughly once every three centuries — it doesn’t happen every season, but it does occasionally, and they will produce an egg. The benefit of that is regardless of gender, any member of the Kuchiki clan is able to lay one.”
“That’s pretty cool,” Ichigo acknowledges. “Then it just, what? Hatches on its own?”
At that, Rukia’s eyes get a little misty. “Ah, if onee-san was still alive, then maybe… Well, she would have been able to inject a little of her spiritual energy into the egg. If they were a good match, which of course they would have been, then the egg would have hatched. Eventually. And they would have had a beautiful child with nii-san’s hair and onee-san’s eyes…”
“So it’s kind of like soulmates, but with extra steps. Typical Kuchiki behaviour, overcomplicating things — ow!” Ichigo’s sentence is cut off halfway as Rukia thumps him in the stomach.
Rubbing his stomach, he continues. “But what exactly determines if they are a good match? Some kind of soul magic? And what happens if there’s no one suitable ever? Does the egg… go bad?”
“I don’t know,” Rukia admits. “It’s the first time that nii-san has had an egg. In the whole history of our family, no egg has ever been abandoned. I worry the elders may use this as a way to force him to take a new wife they deem more… suitable.”
*
After managing to fall asleep again and thus be late for morning drills at their respective divisions, Ichigo and Rukia arrive at Kuchiki Manor in the evening to be introduced to their potential niece or nephew. Byakuya is the same as ever, but Ichigo swears there is a slight air of self-satisfaction about him, of pride at have produced an egg, underneath that placid and unflappable demeanour.
It is already pretty good looking for an egg, which is to be expected, what with Byakuya's looks. The shell is pearlescent in colour, reflecting everything around it into vivid, rainbow distortions. Placed on a velvet cushion, it's slightly larger than an ostrich egg, and closer to the size of a small boulder. Ichigo can't hold the question back, he has to ask —
“That… came out of you?” he asks. Rukia steps on his foot and he grits his teeth through the pain.
“It has grown somewhat in size since it was first laid,” Byakuya conceeds. “Yesterday it was roughly the size of a chicken egg. But the records show that Kuchiki eggs grow quickly, and thus far the egg has met all the typical growth milestones that have been observed within the first twenty-four hours. It may yet grow further, but without a suitable partner's energy…”
Byakuya trails off, and Rukia's foot grinds into Ichigo's in a way that is getting to be quite painful, so he hurriedly clears his throat. “I'm sure things will work out,” he says cheerily.
Byakuya hums, and gives the egg a thoughtful look, his finger gently stroking its glossy shell. There are rows and rows of eggs behind him, the shells of former Kuchiki members. Rukia has even shown Ichigo the shell that previously housed Byakuya, a light-pink affair carefully pieced back together with liquid gold. Because of the colour of the egg, everyone had assumed Byakuya would be a girl at first.
The door bursts open and Kyoraku enters, his arms wide open in typical dramatic fashion. “Congratulations, Byakuya-kun!” he says warmly. “I just heard the news and rushed over! I don’t want you to worry about a single thing, I have a wonderful group of suitors — women AND men in mind… all we need to do is organise a fabulous party!”
Ichigo thinks he sees Byakuya pale slightly, and has to stifle a laugh.
*
He has to go back to the Human World for a few days on a quick mission, so he takes the opportunity to visit Urahara and drop off a shipment of whatever he’s ordered now. Ichigo is practically ambushed by the man when he steps into the shop.
“So,” Urahara says eagerly. “We’ve heard all about the egg. What is it like? Do you think Byakuya will mind if I pop over to take a little look? It’s really a criminally understudied area of shinigami science. What did it look like? How big is it?”
Ichigo slams down the heavy box and rolls his eyes. “It’s fine. Yes, I think he will mind. It looked like an egg. The last time I saw it, it was about this high.”
He gestures with his hands to indicate something between the size of a dog and a car tyre. He swears that Urahara shudders in pleasure at imagining it.
“Fascinating. I do hope I get to see it before it hatches. I hear the Captain-Commander is hosting some kind of party in honour of Kuchiki-san, I wonder…”
“It’s probably already happened or happening now. You’re too late.” Ichigo says shortly. He feels a sudden surge of protection for this unborn child, who is going to enter a world of completely insane individuals and death gods. He needs to do everything in his power to make sure that the child does not get into Urahara’s clutches, or worse, turn out like Byakuya.
“So cruel of you not to invite me, Kurosaki-kun… Well, I suppose I can maybe convince Yoruichi-san to go and see the baby and then perhaps she’ll find them so adorable that she’ll finally let me put a baby in her…”
“Soi-Fon would kill you first,” Ichigo says flatly.
“Yes well, I didn’t say it would be my baby. Please, Ichigo, I’m hurt that you think I wouldn’t be able to figure out something as simple as allowing two women to have a child. That stuff is easy. Watching someone try to give birth as the child claws its way through their mouth is where the real scientific work lies. I just don’t understand why Yoruichi-san won’t agree to it. I can guarantee she won’t feel any pain!”
Ichigo has to suppress a gag at the image. “Yeah, not like that’s a good enough reason to not want an entire child emerging from you the wrong way round.”
Urahara mutters something about the glory of the pursuit of science, which Ichigo cheerfully tunes out.
*
“Ichigo! Terrible news!” Rukia wails, throwing herself at him when he re-enters Soul Society.
“What is it? Did something happen to the egg?” Ichigo demands.
“The egg is fine for now, but— but!”
When he finally gets Rukia to calm down, the whole story comes out. Apparently Kyoraku’s idea of a party with lots of excellent suitors was really just a gathering of all the captains and lieutenants for a massive drinking session at Kuchiki Manor. The drunker people got, the more curious they were about the egg. Eventually Kenpachi had shouted that he wasn’t a pussy, and that between him and Byakuya they might be able to produce the strongest child alive. Renji had leapt to his captain’s defence, and somehow, according to Rukia’s own garbled memory, they had ended up trying to outdo each other, both pouring as much spiritual energy as possible into the egg. By the time Captains Hirako and Muguruma had managed to drag them away, it was too late. The damage had already been done. Clearly someone’s spiritual energy had taken root, because the egg had changed colour, and something within it was definitely pulsing, like a heartbeat had been started.
Where had Byakuya been in all this? Well, the Captain-Commander had plied him with so many drinks that he had passed out about halfway through. Definitely, Rukia emphasises, from the stresses of his potential child and not being able to find someone with suitable spiritual energy, because nii-san wasn’t the kind of man who got sloppy drunk!
“Oh god,” Rukia says. “I haven’t even broken the news to nii-san yet, he’s still recovering from his hangover! What if the child turns out to be Kenpachi’s? How will nii-san live with that brute? He’ll have to marry him to satisfy the clan’s honour, and while Yachiru is adorable… the baby is going to grow up to be a menace!”
“There is someone who will be able to find out who the other father is, don’t worry about that,” Ichigo says grimly. “You… go and tell Byakuya what happened. I’ll go and find Renji.”
*
As it turns out, Renji and Kenpachi are already in a bar, drinking and coming to terms with the consequences of their actions. Ichigo had been anticipating needing to pull them out of a fight for whatever reason, but it seems there might be other problems at hand.
“Ichigo…” Renji weeps, collapsing onto his friend’s shoulder “I’M NOT READY TO BE A FATHER!”
“There, there,” Ichigo says weakly. On his other side, Kenpachi is deep in his cups, muttering to no one in particular and waving his sword as usual.
“Gotta give Yachiru a siblin’,” Kenpachi slurs.
“Captain Kuchiki is so… is so perfect!” Renji wails, shaking Ichigo so hard he has to grit his teeth to avoid them being shaken out of his head. “What if the child turns out STUPID like me?”
“If it’s another lil’ girl, she an’ Yachiru can go out and kill Hollows together!” Kenpachi says to no one in particular. “An’ if it’s a lil’ boy, Yachiru can also teach him how’ta kill Hollows!”
As soon as Ichigo can escape, he does. No sense in sticking around with these two lunatics. The faster they figure out who the actual other father is, the quicker they can put this nonsense to rest.
*
While discussing their options, unfortunately Urahara is the best choice. Mayuri was asked, but he refused, saying he wanted nothing to do with it unless he could experiment on the child. Obviously that was a no-go, and at least Urahara doesn’t have any horrible requests, or at least can be trusted to carry them out slightly more humanely.
It takes all of about twelve hours for Urahara and his haphazardly cobbled together paternity-reiatsu-determining-device to retrieve an answer, and when he does, he calls all the concerned parties in — and everyone files into the small room where the egg is held.
Byakuya’s face is calm, but Ichigo can feel the undercurrent of concern beneath it, having become quite accustomed to the micro-expressions over the years. Renji and Kenpachi stand to the side, still very obviously fucking hungover. Rukia’s arms are crossed as she shakes her head disapprovingly over the whole scene.
“Well, it’s really fascinating stuff,” Urahara says. “Did you know that the egg has it’s own unique genome? Also, the shell is made almost entirely of condensed spiritual energy. That’s not surprising, but it’s the way that the fusion of two spiritual energies which are battling and then trying to merge with each other interact that’s—”
“Urahara,” Byakuya growls, his hand wavering on Senbonzakura. Ichigo has to hold Rukia back from jumping on the shopkeeper. “Please take this seriously. The fate of my child lies in your hands.”
“Right, right,” Urahara says waving his fan. He takes out a comically large envelope and, fuck, Ichigo knows where this is going. He wants to stop it but also it’s probably too late for that now, Urahara probably has a back up. Renji and Kenpachi start to look particularly worried.
“In the case of the as of yet unborn Kuchiki heir…” Urahara declares, reaching into the envelope. “ABARAI RENJI, YOU ARE THE FATHER!”
The joke lands like a rock at first as everyone processes the news, then the room erupts into cheering and clapping. Everyone lines up to slap Renji on the back and ruffle his hair. Kenpachi looks disappointed, but just scoffs and storms out of the room. Renji is more stunned than anything, allowing himself to be pushed and pulled around. Ichigo gives his friend a hearty slap on the back and a grin.
“You’d better take good care of my brother,” Rukia warns, but Ichigo can tell that she’s relieved too, that for all his fears, Renji is a good, strong, dependable guy.
The room parts when Byakuya finally approaches.
“Uh, Captain, I—” Renji is blushing so hard, his hands shaking.
“You will be formidable Kuchiki consort,” Byakuya says simply. “But you have much to learn. We need to get started on your lessons in etiquette immediately.”
Ichigo can’t stop grinning. At least with Renji around now, he’ll have one interesting brother-in-law to hang out with during all those boring Kuchiki family parties.
A sudden shifting and a crack from behind them. Everyone turns around to look at the egg, which has a thin dark line running down it now.
“Oh goody!” Urahara chirps. “It’s hatching!”
*
BONUS SCENE:
“You’re telling me, Byakuya was the one who was behind all this? The timing of the egg, the drinking competition, the paternity test?” Ichigo hisses at Rukia.
They’re watching Renji coo over the baby, a little girl with grey eyes and a shock of dark red hair. Byakuya hovers over them with — does Ichigo’s eyes deceive him? — what looks like an actual smile on his face.
“Well, nii-san didn’t say all that outright, but he implied it,” Rukia shudders.