There was a knock on the door of the Sakai Family's apartment. A man named Makoto answered to find his neighbor Inko Midoriya standing there with her two-day-old baby boy in her arms.
"Hello Makoto. I was wondering if you guys would like to meet little Izuku." Inko said to him.
"Of course! Come on in!" Makoto welcomed his neighbor and her baby inside his apartment. Inko was a close friend of Makoto and his wife Aya since they had been neighbors for years.
"Aya Honey, Inko is here and she brought baby Izuku over." Makoto called out to his wife who was in her two-month-old daughter Yuna's room waking her up from her nap. She lifted the infant up out of her crib and carried her to the living room where her husband and neighbor were waiting.
"Why hello Inko. Welcome back from the hospital. So this is Izuku, huh? He's so adorable!" Aya greeted Inko.
"Why thank you." Inko said as Izuku babbled happily in her arms. The noise of a fellow infant caught little Yuna's attention and she started to get vocal too. She began reaching in the direction of Izuku's voice.
"Looks like Yuna wants to meet Izuku." Aya said as she brought Yuna over to Inko and Izuku who got more excited when he saw the dark brown-haired infant getting closer. He reached towards Yuna and she continued to do the same. When they were close enough, they grabbed each other's hands and giggled. Izuku stared into Yuna's teal-colored eyes as she stared back into his emerald ones. The three parents chuckled at the adorable meeting.
"Aww they already like each other." Inko said as she smiled at the two babies happily playing what seemed like their own version of patty cake. The parents chatted for a while as the two babies played with each other from their mother's laps. When it was time to leave, Inko stood up with baby Izuku who started to cry from being pulled away from Yuna who also began to whimper because her new friend was leaving.
"Oh no Yuna, don't cry. It'll be okay. Izuku will be back." Aya said to her daughter while trying to calm her down.
"Inko, you're welcome to bring Izuku over anytime." Makoto said to Inko who was still trying to calm down her baby boy.
"Shh shh, it's okay Izuku. You hear that? You'll see Yuna again soon." Inko said to sooth her little boy as she cradled him in her arms. Both babies started to calm down. It was as if they understood what their parents were saying.
~Time Skip~
Over the years, Yuna Sakai and Izuku Midoriya had frequent play dates due to their parents bringing them with whenever they visited each other's apartments as friends. As they grew up together, they became quite fond of each other, even attending the same kindergarten. They were pretty much inseparable and were together whenever their parents allowed them to be. It was now June 4 and Yuna Sakai just turned four years old one month ago on May 4. Izuku was close to turning four, his birthday being on July 15. They were on a play date at his apartment while Yuna's father Makoto was at work and her mother Aya was running errands. They were playing one of their favorite games where they dressed up as heroes and went on missions together. Izuku wore his All Might costume over his clothes and Yuna had her blanket tied around her neck.
"Good work Teleportia! We captured the villain and put him in jail!" Izuku said as he put a figurine under an overturned laundry basket. Teleportia was Yuna's hero name for this game. She didn't have her own quirk yet so she just pretended she had her dad's quirk. Her father Makoto worked as a professional hero. His quirk was Teleportation. He could teleport himself, people, and/or objects to any place that he'd previously been. Her mother Aya was currently a stay-at-home mom. She used to be a professional hero but quit once Yuna was born so she could take care of her. Her quirk was Pocket Dimension which allowed her to open portals to different dimensions. And she could use those portals to store objects of any size and had access to them at all times. Yuna always wanted to be a hero just like Izuku did. They had a lot of fun pretending to be heroes. They both admired them, especially All Might. Suddenly, the door to Izuku's room opened and Inko walked in.
"Alright you two, it's lunch time!" Inko said as she led the two children to the kitchen table where she had sandwiches ready for them. Yuna and Izuku ate quickly then went back to Izuku's room to continue their play date.
"So what do you wanna do Yuna? We already did what I wanted to do. So now it's your turn." Izuku said as Yuna looked over at the book shelf in his bedroom. There, Izuku had a collection of picture books, graphic novels and comics. Yuna picked out one of the graphic novels with All Might on the cover.
"Let's read this!" Yuna said as she untied the simple loose knot of her blanket around her neck and took it off.
"Okay!" Izuku said as he took off the All Might costume he was wearing over his clothes and lay down on his stomach next to her, grabbing his All Might doll that was nearby. Now Yuna couldn't exactly read yet, so she narrated what she thought the words said based on the pictures on the panels. Izuku loved listening to Yuna "read" out loud. It was relaxing and fun.
"... The heroes were having trouble with a strong villain and were about to give up. Just then, All Might appeared and said 'Have no fear, because I am here!' Then he rushed into action and took down the villain with one punch! The villain was arrested and people crowded around All Might and cheered. The end." Yuna said as she traced her finger over the last of the panels and closed the book. Izuku sat up and pumped his fist in the air.
"Yes! All Might is the best! I wanna be just like him!" Izuku said excitedly.
"Yeah, that would be awesome! I wonder what quirk I'm gonna get. I hope it's just like my dad's quirk. But getting Mom's quirk would be cool too. Or better yet, a combo of the two!" Yuna said with equal excitement as Izuku.
"What about you Izuku? What quirk do you think you're gonna get?" Yuna asked her best friend. Izuku thought for a moment.
"I don't know. My mom can float small objects towards her and apparently my dad could breathe fire. Whatever quirk I get, I hope it's just as cool as Kacchan's quirk." Izuku answered as he recalled the day Katsuki Bakugo's quirk manifested at school. It was a couple days after he turned four. Then he remembered something.
"Hey Yuna? You just turned four one month ago so you should be getting your quirk soon." Izuku said as his eyes lit up, excited for his best friend who chuckled.
"Haha yeah. Hey, wouldn't it be funny if I got my quirk today?" Yuna asked Izuku.
"Maybe you should try teleporting or opening a portal to see if you can." Izuku suggested as Yuna smiled in excitement at the idea.
"Okay! Let's see... My mom just holds out her hand in front of her to open portals. Let's try that first." Yuna said as she held out her hand and tried to open a portal but to no avail.
"Aww bummer. Looks like that didn't work." Izuku said as Yuna sighed in disappointment. Then she thought for a second on how her dad activates his quirk.
"Hmm... My dad puts his pointer and middle fingers to his forehead and closes his eyes when he teleports." Yuna said as she touched her forehead with her right index and middle fingers and closed her eyes. Nothing happened again. Both her and Izuku were bummed out. Then he came up with an idea.
"Maybe try doing it with your left fingers. You always draw with your left hand." Izuku suggested as Yuna's facial expression brightened.
"Well my dad uses the fingers on his right hand. He's right-handed, unlike me and my mom... Wait a second... Izuku you're a genius!" Yuna said as she touched her left index and middle fingers to her forehead and closed her eyes. When she opened them, she was in a strange place she didn't recognize. She was in a grassy clearing surrounded by woods.
"Hey it looks like it worked!" Yuna said excitedly while jumping up and down. She ran around in circles, spreading her arms out while laughing. Then she tried going back home the same way she got there. But nothing happened. She was stuck in this new unfamiliar place and it scared her. Yuna began to cry, afraid that she'd never see Izuku or her family again. The noise caught the attention of a huge black pearlescent dragon with rainbow iridescent belly scales, horns, and claws. His wing membranes looked like an iridescent sheet of vinyl. He approached her as to investigate. When she noticed him, she stopped crying, and froze in fear. Realizing he had frightened her, he spoke.
"Do not be afraid. I am not going to hurt you. What is your name?" The dragon said to Yuna in a deep voice.
"My name's Yuna... Yuna Sakai. Wh-where am I?" Yuna said, wiping the tears away from her face.
"Why you're in the Fiore Kingdom of course!" The dragon said with a chuckle. Yuna just stared at him with a puzzled look on her face.
"Fiore... Kingdom?" She said as the dragon seemed surprised at her confusion.
"Yes, the Fiore Kingdom. Are you not from here?" The dragon asked Yuna nodded her head shyly.
"I'm from the country of Japan on a planet called Earth." She answered the dragon who looked perplexed.
"Earth? You mean Earthland? Even so, I've never heard of a country called Japan." The dragon said, scratching his chin with his claw.
"I'm not from this universe. My quirk... it must allow me to teleport to another universe. But it only seems to be one way." Yuna said as the dragon seemed to get even more confused.
"Quirk?" He said as Yuna began to explain everything to him.
"Ah I see. Well there are no quirks here, but there is magic. Lucky for you, I know how to manipulate different dimensions and have visited many different worlds in my time. Most of which do not welcome me and attack immediately. I have made many enemies in other worlds so I stopped using my magic long ago and just live peacefully here where I originated. I can take you under my wing and teach you this magic. Once you are strong enough, you may be able to go back home." The dragon explained to Yuna who broke into a bright smile.
"Really? Thank you... umm..." Yuna trailed off as she did not know the dragon's name.
"Oh, sorry. I haven't properly introduced myself. Where are my manners? My name is Planeus, the Great Dimensional Dragon." Planeus introduced himself to Yuna.
"Thank you Planeus. You're so kind." Yuna said as Planeus chuckled at her compliment.
"You're different from the humans I've encountered in other worlds and even most of the humans of this world." Planeus said to Yuna.
'I'm starting to see what Igneel meant when he was talking about Natsu Dragneel.' Planeus admitted to himself mentally.
~In the MHA/BNHA Universe~
Yuna had just disappeared right before Izuku's eyes. His idea worked and she activated her quirk! Now he needed to go find where she went. He began searching his apartment for her. But he couldn't find her anywhere. He started to panic as he continued the search for his best friend. His mom noticed him looking around the apartment frantically and approached him curiously
"What's wrong Izuku?" Inko asked her son.
"Yuna used her quirk for the first time and she teleported somewhere, but I can't find her anywhere!" Izuku said as Inko's facial expression went from one of curiosity to worry. She immediately called Yuna's parents and notified them of the situation. Together, Yuna's parents Makoto and Aya, Inko, and Izuku looked for her. Based on Izuku's eyewitness account, she seemed to have used teleportation. They assumed that Yuna had teleported somewhere she had been before since that's how her dad's quirk worked. They called the police and asked for a search party to help find her. But unfortunately, she was nowhere to be found. Izuku was teary eyed as Inko put him to bed.
"Mom? Do you think they'll ever find Yuna?" Izuku asked his mother who mustered a smile.
"Of course they will Sweetie. I'm sure she will turn up." Inko said to reassure her son.
"I miss her already." Izuku said as he started to sniffle and tears began to roll down his cheeks. Inko pet Izuku's soft and fluffy green locks reassuringly.
"I know you do. But don't worry, she'll turn up again." Inko said with a smile as she got off his bed and turned off the lights and shut his door. That night poor Izuku cried himself to sleep missing his best friend dearly.
~In the Fairy Tail Universe~
It was nighttime in Earthland and Planeus had brought Yuna to his cave where he lived. He curled up on a pile of cleaned furs, probably made from his meals.
"It's late. You should get some rest kid. You can sleep next to me." Planeus said as he lifted his huge wing for Yuna to craw under which she did. She grabbed one of the furs and draped it over her body like a blanket and leaned her head against his side. Planeus lowered his wing and it covered Yuna like a tent. It was warm and unusually cozy underneath his wing and Yuna quickly fell asleep. She dreamed of seeing Izuku and her family again. Tears rolled down her cheeks as she whimpered in her sleep, longing for the day she'd return home.