I had two random fanfic ideas. Instead of writing each of them separately, I decided to toss them into the blender and put them together. I… am responsible if this story is a train-wreck and nobody likes it.

Izuku ran through the doors of the hospital, panting. He'd just come from school, where a message from his mother had been waiting on his phone during lunch.

It's time.

"No running!" barked one of the nurses as he passed her. He slid to a stop in front of the receptionist desk.

"I'm… looking for Inko Midoriya!" he gasped out. The nurse checked her computer and smiled.

"Third floor, room thirteen. Fourth door on your left when you turn right."

He picked up the pace again, heading straight for the elevator and finding his way to the room without much issue. Just outside the door, he paused. On the other side of this door was something that would mean he and his mother weren't alone anymore. A sign that he had a use to somebody other than scorn. Was he ready? No. But there was no turning back. Taking a deep breath, Izuku opened the door and took in the sight before him.

Inko was sitting in the hospital bed, a pale pink blanket in her arms with a tuft of green hair poking out. Izuku closed the door and walked over to his mother, setting down his backpack.

"Izuku, meet your little sister," Inko whispered.

He slowly walked forwards and looked at his little sister's face. She had the roundness that he and his mother shared, and the messy hair he shared with his father. But what caught his attention the most was just how tiny and helpless his baby sister really was. Her eyes fluttered open and he could see that they were blue; he'd known they would be from a lack of melanin production, but they'd turn to their natural color soon.

"Did you name her yet?"

"You came up with a few good ones. What do you think?" Izuku reached into his backpack and pulled out the notebook he'd set aside for naming his younger sibling. Names covered the pages, but one caught his attention and he knew that was the one.

"Miharu."

"Miharu. Miharu Midoriya. It's perfect." Inko smiled down at the baby, then at Izuku. "Do you want to hold her?"

"I'd love to!"

She gently handed the newborn off to him and he held her to him just as carefully.

Miharu. There's a lot you don't know about the world yet. There's a lot I don't know, too. But I'm going to do my best to be a brother you can be proud of. Even if I don't become a pro hero, maybe I can be somebody you look up to the way I look up to All-Might.

Yeah. I'm going to be the best big brother ever.

And nobody can say otherwise.

Miharu wiggled in her blanket and let out a gurgle.

"She's perfect, Mom."

"Well, she's your sister. And I expected you to love her."

"I'm gonna do my best to protect her. From anything that might hurt her."

"She looks stupid."

"KATSUKI!" Mitsuki smacked her son on the back of the head.

"What?! She's just been born and she's already a wrinkly little hag!"

"You did, too, when you were born!"

Izuku couldn't help but smile.

The Bakugo family had come over to see the baby once Inko had come home from the hospital and while Mitsuki and her husband fawned over the new baby, Kacchan was less than impressed. It didn't bother Izuku; unless it was an amazing Quirk, few things impressed Kacchan. Particularly when it came to the Midoriya family. Miharu was no exception. Of course, Izuku was always reluctant to leave his baby sister alone, which simultaneously made Inko laugh and sigh.

"She already has you wrapped around her finger."

"I bet she's gonna be Quirkless, too, just like Deku," Kacchan muttered under his breath.

Izuku chose to ignore that comment. Besides, Miharu would more than likely have a Quirk. And if she did, he'd do his best to make sure she could use it and make it wherever she wanted to. Whether it be UA or some other school, Miharu would have far more opportunities than her Quirkless older brother.

"Zuku!"

Miharu ran to the front door as soon as she heard it open. Izuku came through and took off his shoes before giving her his customary 'I'm Home' hug.

"Were you good for Mom today?"

"Uh-huh! Did meanie Kacchan hurt you?"

"No, he didn't. Trust me, Micchan."

She gave him a look before running to the living room.

It was hard to believe Miharu was already three years old. She was tiny for her age, with the same green hair as her mother and the same freckles as her brother. No Quirk had made its presence known yet, but it was only a matter of time. The only mystery about Miharu was her eye color—a striking blue that Izuku couldn't think of anybody having.

As for her and Izuku's relationship, Inko had been correct; Miharu had Izuku wrapped around her little finger and he was willing to do anything for her. She was a bit more quick to anger—mostly when Kacchan was making fun of her brother—but she was also one of the sweetest kids Izuku had ever met. Not to mention she'd latched onto his All-Might obsession to the point where she asked their mother to play that same old video over and over again, just like he had.

He wondered what she'd think if she knew All-Might was training him.

She'd probably want to come with me… and he'd probably carry her because he's All-Might.

When he got his Quirk and came home depressed because of what had happened at the entrance exam, he ended up going to bed right after dinner. He woke up when he heard his door creak open.

"Zuku?"

"What's wrong, Micchan?" She came over to his bed and struggled to get onto it. Like a good big brother, he helped her up.

"You're the best big brother ever. If UA can't see that, then… then… they're meanies!"

"Heh. Thanks."

"Can I stay in here?"

"Of course." She snuggled up next to him and he let her under the blanket. "You know, Micchan, Kacchan was taking his entrance exam today, too."

"I hope he failed."

"Micchan!"

"He's a meanie! You can't be a hero if you're a meanie!"

"He's strong, though."

"I'm stronger." She puffed out her cheeks.

"Yeah, you are." He pulled her into a hug and started tickling her. She shrieked and laughed as she tried to push him off her.

And on the day his results arrived, Miharu waited patiently outside his room with their mother, who was pacing anxiously. Izuku came out of his room to find his two female family members waiting for him.

"I... I made it."

Miharu gasped.

"I'm gonna be a hero!"

"YAY, ZUKU!"

He picked up his little sister and swung her around in excitement as they both cheered.

"Hello?"

"It's been a while, hasn't it?"

"Inko? How are you?"

"I'm fine. I'm sure you know already, but… Izuku made it into UA. We got the notice today."

"I knew he'd do fine. You had him sticking to the plan, right?"

"Of course. He's been doing so well lately."

"How's Miharu?"

"She's just as excited as Izuku about the results. I wish you could see her…"

"I do, too. Trust me, I want to see my little girl. But it's not safe."

"Miharu idolizes All-Might as much as Izuku does, I'll have you know." There was laughter on the other end.

"Let me guess—the video?"

"The video." Inko laughed. "They're both asleep right now, but I'm sure she'll be asking me or him to play it for her tomorrow morning."

"Are you sure you're gonna be okay with Izuku going to UA? I… I know you worry about him."

"It'll be a little lonely with him being with his classmates and doing more schoolwork than ever, but I have Miharu."

"She'll keep you on your toes."

"I'd better head to bed myself. I… I love you."

"Love you, too. Good night, Inko."

"Good night, Toshinori."

So this is an AU where two things are happening. One, Izuku has a younger sister named Miharu (on the timeline, she's three when Izuku is fourteen. Do the math). And two, All-Might is their father. This is just a random idea I had. Don't ask when Inko and Toshinori met up to make Miharu. Just… just don't.

Next chapter, we'll see the Sports Festival as well as Izuku's classmates meeting Miharu. Cue every girl in class thinking he's the sweetest guy ever.

So long and thanks for all the fish!