For the sake of the story, Rize is five years older than Kaneki. You'll see why in a bit.

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Rize Kamishiro was sitting at one of the tables in Anteiku, reading The Egg of the Black Goat. She had read the book so many times but she still felt at home in the pages. She'd been in a sort of funk lately, and she couldn't even figure it out herself. She didn't even feel like eating, only having eaten two people this month.

A scent passed by her nose, and her eyes widened. The scent was familiar, so much so that it was scary.

She snapped her book shut, putting it in her purse. She dropped some money on the table before leaving in a hurry, rushing out the door and drawing several looks.

Touka narrowed her eyes. Rize had a sense of smell that was uncanny, even to ghouls. For her to run out like that, she must have smelled something extraordinarily interesting.

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Rize ran through the streets, following the scent between buildings and through alleys. Every time she thought she was about to find the source, it got even stronger and led somewhere else. She was growing frustrated, this scent was the same one from her early memories, she had to find it.

But it was stronger now. The aroma was so potent to her that it was like someone sprayed copious amounts of a cologne made just for her. The sweet smell of human mingling in with the bitter scent of ghoul, there was nothing more spectacular.

Rize came to a small park for an apartment complex, and tried to follow the scent further. But the trail stopped here. She looked around to see a young man with white hair sitting on a bench, face buried into the very same book she had been reading earlier. He was dressed in a handsome grey suit, not unlike what ghoul investigators would wear. She hesitated at that thought, but walked forward when she couldn't see a Quinque case.

Kaneki was absorbed in learning the kanji on the page, but stopped when he felt someone behind him. He turned around on the bench to see a ghoul with purple hair staring at him strangely. But there was something familiar about her.

"What do you want?" he asked sharply.

Her eyes misted up as she stared at him, and she gave a mix between a sob and a laugh, "It's really you."

Kaneki was confused now, but went on guard when she started walking towards him. He stood up quickly, dropping his book in the process, "Don't come any closer."

She ignored him, walking even faster. Kaneki had enough and formed a red tentacle, launching it at her.

And she blocked with the exact same Kagune.

Kaneki's eyed were impossibly wide, and he formed three more, "No way. No fucking way. HOW DO YOU HAVE MY KAGUNE!?"

Rize looked at him with a teary smile, "It's okay, I don't want to hurt you. I could never hurt you, Otouto."

Kaneki froze, staring at her in disbelief, "What did you just call me?"

Rize was close enough to touch him, and did so, placing a hand on his cheek. She stared at him for a moment longer, before answering his question, "You are my little brother. Kaneki Ken. You know, at first I thought it was folly when mom broke up with my biological father, and started dating a human. I hated him at first, but you changed that. When mom gave birth to you, you were my whole world. I was five years old when you were born, and I never had any friends. You were my first friend."

Kaneki remained silent, in shock from what she was telling him.

"But it all ended too quickly." Rize said, her smile gone, "When you were about three, CCG found out about mom, and killed dad because he was married to a ghoul. I was at school, but mom was at home with you."

She choked back a sob, "When I got home, Mom was dead. And you were gone. I had lost everything in the span of one school day."

Kaneki kept staring at her, before enveloping her in a hug. Rize looked at him in surprise. He was crying.

"I actually have a family. I have a family. I have a sister. I had a mom. I had a dad." Kaneki said with a shaky voice, "All this time, I thought I was grown in a vat be CCG, that I was created as a living Quinque. When they punished me, I told myself that they were just sharpening me, that I was just a knife for them to use."

Rize's eyes turned red and black, "Punishment? What punishment?"

Kaneki pushed her away and started breathing heavily, crawling under one of the picnic tables in the park.

"My fingers on the bench. Centipedes in my ears. In my HEAD!" Kaneki screamed as his Kakuja formed, throwing the table aside, the centipede tails flailing wildly. He looked at Rize with panic, "1000 minus 7, 993, 986, 979, 972, 965..." he trailed off, going catatonic.

Rize embraced him, "Everything will be alright. They won't hurt you again." Her eyed hardened behind his back. Everybody knew what had happened to Jason, and this matched perfectly. The telltale signs of PTSD were all there. On the other hand, Kaneki also had a Kakuja. That comes with a large price, and judging by the shape it took, her little brother was the feared Centipede of CCG. A bogeyman that nobody was ever able to prove existed. Mainly because all of the alleged sightings left no survivors.

She calmed him down, his Kagune vanishing as he became silent. He needed a place to stay, and she knew just the place.

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Touka was wiping out a cup when the door opened. It was closing time, and she went to tell that to whoever walked in, but her eyes widened in surprise and the words never left her mouth.

Rize walked through the door, carrying a sleeping Kaneki in her arms. At first, Touka thought that Rize had somehow defeated him. But he wasn't injured, and she was carrying him far too carefully for him to be an enemy.

"Is Yoshimura in?" Rize asked, "I need to ask a favor."

Touka tore her eyes away from the sleeping ghoul, "What are you doing with him, Rize? Either kill him or take him away from here, he's a monster."

"What he is is none of your concern. Where is Yoshimura?" Rize responded firmly.

"Right here, Rize." Yoshimura said as he walked out of the back, "What is it you need?" his eyes landed on Kaneki, and he narrowed them, "What is the reason for you bringing this young man here, Rize?"

Rize looked at his sleeping face, "I need a place to hide my little brother. He escaped from CCG, so I know they'll be looking for him."

Everybody in the cafe stopped what they were doing, even Yoshimura had wide eyes, "I was unaware that you had a younger brother. That he just happens to be the ghoul I drove off the other day is extraordinary."

Rize looked at him, "So you fought him, huh? Then you should know that having him on your side is a good idea. In exchange for shelter for Kaneki, I will join Anteiku. Just please let him stay here."

Touka looked back and forth between Yoshimura and spoke up, "You aren't seriously considering it, are you? You're the only one of us who can fight him. He could kill us all if he wanted to!"

Yoshimura looked to her, "You should know that I am still a fair bit stronger than this child. Besides, what would you do in Rize's shoes, Touka? If you had an opportunity to save your little brother from CCG, would you not take advantage of it?" he looked back at Rize, "He is welcome here, but he will lose that privilege should he step out of line. And I expect you to work for his room as well. He is welcome to as well, but I have a feeling he will need some time to get used to the change of scenery."

Rize smiled gratefully, walking up the stairs to where she knew the guest rooms were.

She opened the unmarked door while still holding Kaneki, and laid him down on the bed inside. She looked at him for a moment before closing the door and sitting down on the small sofa next to the bed.

"Sweet dreams, Otouto."

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So first of all, I put AU into the description so people don't yell at me in PMs again, despite the fact I thought it was a fairly obvious AU.

Kaneki is a natural One-Eye, and shares the same mother as Rize, thus their Kagunes are almost identical. Kaneki's father was a human, and their family was killed by CCG when Rize was at school. Kaneki was kidnapped by CCG due to his hybrid status, and they molded him into a weapon for exterminating ghouls.

That about sums up his origins, Review with any ideas you may have or just tell me what you think of my new story.