"Mom—" As soon as the door of the apartment was opened, the lively voice of Miyano Akemi rang out, and the black-haired little girl ran over holding the brown-haired little girl's hand.

Miyano Elena squatted down and rubbed the heads of the two little girls, then pulled Kudo in front of her with a gentle expression, "Shiho, Akemi, this is Kudo Shinichi. He will be staying at our house temporarily from today."

"Huh?" Miyano Akemi turned her gaze to Kudo Shinichi and circled around him in confusion, "Did mom give birth to a little brother?"

Kudo:?

"No, no!" Kudo shook his head quickly, "My name is Kudo Shinichi. Because my father couldn't find me, I asked Sister Miyano to bring me back and stay here temporarily!"

He didn't want to be misunderstood in any way, in case it affected their family harmony or something.

"Hmm?" Miyano Akemi pulled Miyano Shiho to look at Kudo, and finally asked with a serious expression, "How old are you, Kudo?"

"Seven years old." Kudo answered with a hint of pride.

He is seven years old this year. He is no longer a kid, he is already an adult!

"Yeah, my name is Miyano Akemi, and I'm ten and a half years old!" Miyano Akemi breathed a sigh of relief, patted her chest and said, "This is my sister, her name is Miyano Shiho, and she's nine years old this year."

The little girl couldn't hide her happiness and said, "You two have to call me sister!"

Kudo looked at her, puffed up his cheeks and turned his face away, "I don't want to."

"Huh?" Miyano Akemi was stunned. "Why?"

Miyano Shiho remained silent the entire time, like a little wooden block.

"No reason." Kudo shook his head, "I don't call you sister anyway."

What a joke! He is already seven years old! He doesn't want to call a girl "sister"!

"Do you still want to call a boy sister?" Miyano Shiho suddenly asked.

Hmmmm?

Kudo was stunned for a moment, "I didn't say that."

"You just said it. You said you don't want to call a girl "sister." Miyano Shiho hugged Miyano Akemi's arm, obviously protecting Miyano Akemi.

Miyano Akemi looked very frustrated.

Is she a failure as a big sister? Otherwise, why doesn't the new little brother want to call her big sister?

"Hey, boy's childish competitiveness." Miyano Shiho sneered.

"?" Kudo retorted without hesitation, "I didn't!"

"Then why don't you call me sister?" Miyano Shiho stared at him, "Also, I'm older than you, so you should call me sister too."

"...Me!" Kudo blurted out the beginning of his argument, but he couldn't say anything to refute it.

Why don't you call me sister?

It’s because he feels like he’s a little adult and can’t call other girls of the same age “sister”.

His father never called anyone "sister" normally, but he was always forced to call her "sister" by that unreliable mother.

Damn!

"Nothing to say?" Miyano Shiho pressed on, "Then scream."

"I don't want to, unless you compete with me in reasoning." Kudo thought for a moment and said quickly, "Yes! If you solve the answer to the puzzle before me, I will call you sister."