Two weeks ago, at Rinji's family home.

Rinji's father brought him to a dark underground research facility, where Rinji saw the 'sister' floating in the liquid-filled glass container.

Before he could ask questions, his father ambushed him from behind, piercing his back.

After extracting a red gemstone from his body, Rinji fell to the ground, eyes vacant, in a pool of blood.

Holding the bloodied gemstone, Rinji's father slowly approached the girl floating in the container, a gentle smile on his face.

"Time's about right. It's been sixteen years since we last spoke, Chaos."

He brought the gemstone close to the container.

The red gem suddenly sparked with crimson lightning, flowing into the girl's body through the container.

In that instant, the girl's eyes opened, her pupils glowing a blood-red hue.

Boom!

The container exploded, shards scattering across the floor.

The liquid flooded out, and the soaking wet girl stepped out of the broken container.

Upon seeing Rinji's father, a joyful smile appeared on her face.

"Daddy!!"

She ran forward and hugged him tightly.

Rinji's father gently stroked her golden hair, smiling. "My dear daughter, long time no see."

---

Rinji's reunion with his sister marked the beginning of a new chapter in his life.

"Mm!"

The two of them stood there for a moment. After letting go of the girl, Rinji's father turned and smiled.

"Son, this is—"

Before he could finish, a fist suddenly expanded in front of his face.

Bang—

One punch landed squarely, sending Rinji's father flying.

"You bastard, you ambushed me!"

"Dad!"

The girl watched anxiously as her father arced through the air, while Rinji, covered in blood, stood perfectly fine and alert.

"Ugh…"

Holding his nose, Rinji's father stood and walked back up to him. "To strike your own father so hard, you unfilial child."

"And what right does a scumbag father who pierces his own son from behind have to say that to me?"

"Does it hurt?"

"No."

Rinji touched the spot that should have been pierced, now completely intact.

"But it's frightening to do that without a word, you know?"

"You really are petty," his father muttered, rubbing his nose.

"Don't you feel your strength has increased a lot?"

"Well… indeed."

Rinji clenched his fist.

Since earlier, it felt as if he had endless power. Previously, hitting his father was difficult, but that one punch just now had sent him flying—though thankfully, his father wasn't hurt.

"What caused it?"

"Because the thing that's been feeding off your nutrients was removed."

"Ah?"

"Let me introduce you—this is your sister." His father pointed to the girl. "The first child of your mother and me, your sister Chaos, or Takamine Reika."

[Note: Rinji is Disaster while his sister is Chaos]

Looking at the beautiful girl who resembled him, Rinji was momentarily stunned, whispering the unfamiliar word:

"Sister…"

"Brother~"

Reika smiled and stepped forward, hugging Rinji tightly.

"Mm…"

Hugged firmly by a sister he had just met, Rinji was speechless.

"Not bad," Rinji's father said warmly, looking at the hugging siblings. "The whole family of four is finally together."

---

"My sister… how should I put it, sometimes she's like a child," Rinji said. "At home, she clung to Dad and Mom, and to me too. Even though she's my sister, not a little sister."

"Then your sister must be very cute."

"Mm, definitely."

"Then why did you just say she's strange?"

"She's extremely smart."

"Isn't that the same as you?"

"There's a difference… just see for yourself."

As they spoke, they reached the front door.

Using a key, they opened the door and saw a girl with long golden hair.

Her hair cascaded to her waist like a waterfall. Her crimson eyes radiated vitality, and her exquisite beauty was unforgettable—even Hayasaka was captivated.

Her face resembled Rinji's (in cross-dress) and their mother, as if molded from the same template.

Reika turned to Rinji with a cold expression and said:

"You're back, my foolish brother."

Hayasaka: "…"

Rinji: "As I said, her learning ability is strong, but she learns everything."

"…What has she learned?"

"Before coming here from home, she watched hundreds of episodes of 'Naruto'."

"…"

Hayasaka had no words, while Rinji handed the cake he bought outside to Reika.

"Sis, I got you a matcha cake."

"Ah, thanks~"

Reika's expression softened as she took the cake with a smile.

"So, she'll be living here for the time being, living with us."

"Mm."

Hayasaka nodded and quietly said to Reika:

"Um, hello, I'm—"

"I know, you're Hayasaka Ai, right?" Reika smiled. "My foolish brother's girlfriend."

Rinji: "Then you can drop the word 'foolish,' you ain't Itachi."

He carried the groceries he bought into the kitchen to prepare dinner, while Reika and Hayasaka sat on the sofa.

"You're Rinji's sister—hadn't you been to Japan before?"

"Just call me Reika, Ai," Reika said with a smile. "I did spend some time in Japan with Dad before, but those experiences weren't very good."

"Eh?"

"So I died."

"Ah!?"

"I was recently revived," Reika said in a way Hayasaka couldn't understand. "This era is really peaceful."

"Ah… yes."

"Are you and brother happy at school?"

"Fairly happy, I guess."

"That's good, I want to see school too," Reika said.

While Reika chatted with Hayasaka, Rinji suddenly turned in the kitchen.

"By the way, sis, you want to go to school, right?"

"Yes."

"Then how about starting tomorrow, you go in my place?"

"Eh? Really?"

"Of course… ah no, you must go in my place," Rinji said seriously.