In theory, Uchiha Byakuya possessed both the Uchiha bloodline and the Washuu bloodline in his body.
You could say it was thanks to the system when he first transmigrated. The Uchiha bloodline went without saying, and the Washuu bloodline definitely wasn't weak either.
A bloodline that capable of "dragonification" was, at least in the world of "Tokyo Ghoul," among the most top-tier.
After all, think about it; the Dragon Orphans born from the Dragon were very likely the true origin of ghouls. A bloodline that served as the origin of ghouls, what more needed to be said?
Moreover, ghouls with the Washuu bloodline were born kakuja. It was important to note; 'kakuja', not 'half-kakuja'. That alone was enough to reflect how powerful this bloodline was.
Innate possession of four kagune types + natural-born half-ghoul + Uchiha bloodline and the Washuu bloodline, half inherited from Yoshimura Eto and half inherited from Uchiha Byakuya, one could say that Aiko's talent was maxed out from the start, the very definition of "extraordinarily gifted."
"She has a kakuhou, so she should be a half-ghoul. And it's not just one kagune, Aiko-chan has all four types."
At this moment, Byakuya spoke.
And right then, Yoshimura Kuzen and everyone from Anteiku came in as well.
"We happened to overhear what you were saying, we hope that's okay?"
Kirishima Arata said immediately.
"It's fine. It's not some kind of unspeakable secret."
Byakuya replied.
"She's a half-ghoul like Eto-san, and she has four kagune! That's unheard of!"
Kirishima Hikari exclaimed in amazement.
Actually, they weren't entirely sure what it meant to have four kagune, just that it was probably really powerful.
"I heard that ghouls born with two kagune are already considered geniuses, far stronger than those with only one kagune. Especially when at the same level, they're basically unmatched."
Koma Enji said.
Irimi Kaya then added:
"But the truth is, until now we've only seen Mayu as someone born with two kagune. And since she hasn't shown her power, it's hard to imagine how terrifying Aiko-chan's growth potential will be, being born with four kagune."
Hoito Roma naturally had a broader knowledge and deeper understanding about the conditions of ghouls born with multiple kagune.
She spoke, "Ghouls born with two kagune usually have some kind of special ability, for example; extremely sharp perception, or being extraordinarily gifted in some physical trait. Aiko-chan, born with four kagune, will definitely be even more incredible on top of that."
"Regardless of all of that, she's a very adorable child."
Yoshimura Kuzen said with a warm smile.
He didn't care whether she had one kagune or many. He only hoped that the little Aiko could stay far away from any killing and live a happy and stable life.
"So this is Aiko-chan…"
At this moment, Mayu peeked out from behind Yoshimura Kuzen.
She had of course come along as well.
She really wanted to meet her "little sister."
"Can I call her Aiko-chan?"
Mayu walked up and asked Byakuya and Eto.
After all, she wasn't truly the daughter of Byakuya and Eto, and therefore not really Aiko's older sister. So she wanted to ask first.
"Of course you can."
Byakuya nodded as he ruffled her hair.
"Mm!"
Mayu happily nodded, and immediately spoke to the little Aiko, "Hello, Aiko-chan."
Though Aiko herself couldn't speak yet and couldn't understand what Mayu was even saying, it seemed she could sense that the girl in front of her was being very friendly, so she also showed a smile.
"Aiko-chan is so well-behaved and smart!"
Seeing this, Hikari couldn't help but exclaim in admiration.
Thinking back to when Touka and Ayato were just born, they had cried and fussed all the time, every day they had to worry about how to calm them down.
"Well, her parents are Byakuya-san and Eto-san. Their bloodlines are already top-tier."
Irimi Kaya remarked.
In her opinion, one was the strongest half-human, and the other was the strongest half-ghoul. How could the combination of those bloodlines not be outstanding?
As time eventually passed and the years flew by..
Uchiha Aiko gradually began to show her exceptional talents, such as an extraordinary ability to learn.
Whether it was learning to walk or talk, she was far faster than any ordinary toddlers would be.
And then there was her perception, she could sense Byakuya and Eto from across a door or even a street, and would immediately call out "Papa! Mama!"
Her physical strength was naturally also beyond the norm.
Aiko-chan was only five years old now, but if rated using the traditional system, she had already reached at least SSS-level.
Because, with her inherited Washuu bloodline, Aiko-chan was a natural-born kakuja.
Just being a natural kakuja alone was already enough to push her rating past SS-level, and her physical capabilities of course far exceeded those of normal ghouls as well.
Add in the fact that she had four kagune...
Byakuya even regularly fed her "RC concentrate" like it was tea.
For natural-born half-ghouls, the stuff had no side effects at all. It was only dangerous for humans and half-humans other than him.
You could say that Uchiha Aiko, in her current overpowered state, already had a kakuja form on par with Yoshimura Kuzen, even without ever engaging in cannibalism.
Being born with four kagune, she didn't even need to bother with cannibalism; she could just keep growing stronger simply by raising her internal RC cell count.
Her kakuja form naturally resembled that of Eto and Yoshimura Kuzen, after all, Eto inherited hers from her father, and Aiko-chan in turn inherited hers from Eto.
Given how absurdly strong she was now, even calling her SSS-level felt like an understatement.
Most of the time, Aiko-chan played over at "Anteiku," and Byakuya and Eto would come back to spend time with her whenever they were free.
These days, they had plenty of time.
"Aiko-chan, have you been a good girl and listened to Grandpa at the café?"
Eto gently rubbed Aiko-chan's chubby cheeks the moment she got home.
Even at just five years old, Aiko-chan's features increasingly resembled those of Byakuya and Eto. Her face was naturally adorable, with a soft, rosy glow to her cheeks.
And under the careful grooming of Hikari, Irimi Kaya, and the others, she looked just like a little princess.
"Yes, I've been very obedient."
Aiko nodded happily.
"Papa!"
At that moment, Aiko-chan ran toward Byakuya behind Eto, opening her arms as if she wanted to be picked up.
Naturally, Byakuya immediately lifted her by the armpits and held her up high, Aiko-chan loved this "lift-up-high" feeling.
With bursts of giggles, she was lifted up again and again by her father as she smiled.