I’m Getting a Little Sister!!

After that, I somehow managed to get them to believe me. 

A lot happened, but for now, the first stage is over. Though I'm pretty tired after just the first stage… 

"Anyway, we'll believe your story. After seeing something like that, we have no choice." 

"Thanks, Dad." 

"So, where's the Demon King's daughter you brought back? She's here, right?" 

"Yeah. I'll bring her now." 

I head to my room on the second floor to call Miyu. 

I knock lightly before entering. 

"Miyu, it's me, Issei." 

Hearing my voice, Miyu peeks out from under the bed, seemingly relieved. 

She was hiding under there!? 

Wait, her face is really red… 

"Miyu? What's wrong? Your face is red." 

When I ask, Miyu pulls something out from behind her back and shows it to me. 

"Issei, do you like this kind of thing?" 

T-that's the ecchi book I hid under the bed! 

Don't tell me she looked inside!? 

"T-this is too early for you, Miyu!" 

I hurriedly take the ecchi book away. 

I was talking with my parents for quite a while… did she look at the others too!? Did she!? 

Anyway, I need to change the subject! 

"M-Miyu. We're going to see my parents now, so come with me." 

"…How did the talk with your parents go?" 

"They believe me for now. The only thing left is about you." 

I take Miyu's hand and head back to the living room. 

"Dad, Mom. This is Miyu, the Demon King's daughter." 

"N-nice to meet you!!" 

Miyu bows. 

She seems really nervous, her voice trembling. 

"Well, have a seat. Mom, get her something to drink." 

At Dad's words, Mom brings Miyu some tea. 

"T-thank you!" 

"Um, Miyu, was it? You don't need to be so nervous. We've heard about you from Issei, so we understand the situation." 

Thanks to Mom's kind words, Miyu seems to relax a little. 

Then, Dad bows deeply to Miyu. 

"Miyu, I'm sorry about what happened to your father, even if there were circumstances! But this guy, despite being a pervert, has a good heart. Please forgive him!" 

Miyu is surprised by Dad's sudden apology. 

He must have thought the same thing I did—that Miyu resents me. 

Miyu smiles and responds to Dad, who's still bowing. 

"Please raise your head. …It's true that my father was defeated by Issei, but he didn't actually kill him. And the fact that I'm safe now is because Issei brought me to this world. So, I don't resent him at all. I know how kind he is." 

Hearing that, Dad sighs in relief. 

With the atmosphere now better, I bring up the main topic of this conversation. 

"Dad, Mom, I have a request. It's about Miyu." 

"What is it?" 

"I want you to accept Miyu as part of our family. For her future, this is the best option. Please, grant my wish." 

I bow my head to my parents. 

Miyu also bows alongside me. 

After hearing such an unbelievable story, their heads are probably spinning, and now I'm making this request. 

It wouldn't be strange if they refused. 

But this is the only thing I can do! 

To protect Miyu, I have to…! 

"Hey, Mom." 

"What is it, Dad?" 

"Issei, who only had perversion as his strong point, has really grown up, hasn't he?" 

"Yes, I'm surprised too. He's become so dependable." 

What I hear are their gentle voices. 

"Dad?" 

I cautiously raise my head and see them smiling at us. 

"Miyu, if you're okay with it, would you like to become part of our family as our daughter?" 

Hearing those words, Miyu lets out a confused voice. 

"I-is that okay…?" 

"Of course, it is." 

Their response is unwavering. 

Both Dad and Mom are smiling warmly at Miyu. 

"…" 

Tears stream down Miyu's cheeks. 

She covers her eyes, her body trembling. 

"Miyu?" 

When I call out to her, Miyu speaks. 

"I'm sorry… but I'm so happy. I never thought I'd be accepted like this…" 

The princess of a defeated country. 

And a demon at that. 

Normally, only despair would await her. 

If she were caught in a human country, she'd either be locked up in a room for the rest of her life or, worst case, executed. 

But now, Dad and Mom have accepted her. 

Of course, they don't know about the war between humans and demons. 

But they're welcoming Miyu, whom they've just met, with open arms. 

Miyu speaks. 

"Can I… really stay here? Can I really become your daughter…?" 

"Can I ask you something too? Will you become part of our family? Will you let us protect you?" 

Dad responds with a question of his own. 

Miyu, still holding back her tears, nods repeatedly. 

"Thank you… thank you so much…!" 

Dad smiles. 

"Miyu, you're part of our family now. You don't need to be so formal. Right, Mom?" 

"Yes, that's right. No need to hold back. If you're okay with it… we'd be happy if you thought of us as your real parents." 

"Yes! Thank you… Dad, Mom!" 

Dad and Mom gently hug Miyu. 

---

"By the way, how old are you, Miyu?" 

"I'm 14 now. I'll be 15 soon, Dad." 

"I see. So that means you'll be Issei's little sister." 

Miyu will be my little sister. 

Wait, 14!? 

She's 14 with that body!? 

She's 14 with such an amazing boobs!? 

As expected of the Demon King's daughter!? 

"So Dad, from now on Miyu's full name is Hyoudou Miyu, right?"

"Yes, Hyoudou Miyu. It's a nice name, isn't it? What do you think?" 

Miyu says her new name aloud. 

"Hyoudou Miyu… Thank you… I'll cherish this name." 

She places her hands on her chest, closes her eyes, and looks around at us before saying, 

"From today, I'm the daughter of this family, Hyoudou Miyu! Nice to meet you!" 

And so, my family has grown. 

Her name is Hyoudou Miyu. 

She's my little sister. 

From now on, our home is going to get livelier… I can feel it! 

---

"Oh, by the way, Miyu, Issei is the embodiment of lust, so be careful." 

"I know. There were a lot of naughty books under the bed." 

Why do you have to say something like that when things were going so well!! 

And Miyu! 

So you did look at the others after all!!