Adapting to Izuku's new quirk was a bit tricky. Although his transformation was energy based, it came with instincts usually attributed to purely physical transformations.
Not all transformation quirks came with related instincts, but it is a common theme for more primal or animalistic transformations to come with them. It was especially odd for Izuku's instincts to be so strong, considering his quirk is seemingly energy based.
Over the course of the a few months after the doctor's visit Izuku's senses developed well beyond that of a normal human. The first month was a tough time, as he struggled to get used to his enhanced senses of taste and smell. Thankfully it wasn't hard to find resources online that had recommended methods to get used to enhanced senses.
In the second month Inko had noticed some odd behavior from Izuku. His gaze tended to linger out of a window, especially at nighttime. He transformed more often at night during this time.
It wasn't until the third month that she realized what was causing this. The cycles of the moon.
Whenever the Full moon would come around Izuku would lean more and more into his wolfish side. Antsy, pacing back and forth, unconsciously becoming his wolf form for periods of time before snapping back to himself as if breaking from a trance.
She had even found him up one night, in his wolf form, just staring out a window, whimpering. She had asked him about it the next day, but he couldn't recall doing so.
It was then Inko was glad she had managed to obtain the Asui's contact information. Having mutation quirks themselves, they were very familiar with instincts demanding things of them.
It was the beginning of the fourth month that they suggested something to her: camping.
Their quirks gave them instincts to be near wet or swampy conditions. These urges tend to be strongest when their bodies are first adapting to their quirks. They had been taking time here and there to go camping nearby to help their daughter Tsuyu get used to her own needs for a particular environment.
At Inko's assertion that she had never done such a thing, they had invited her and Izuku to go with them to their next camping trip, promising to line it up with that month's full moon.
Their first ever camping trip was quite awkward for the Midoriyas, this being their first ever time going on a camping trip.
They spent the weekend leading up to the camping trip going to a local shopping district to load up the Midoriyas with any necessities they may need if they were to ever do their own camping trip. With how far away they live from each other, coordinating any future trips may be difficult. Better to set them up for a two-person trip if it was ever required.
Beru was watching the kids, having them help her set up the chairs and little tables around what the Asui's usually use as a firepit.
The campsite was located not too far from the Asui's home, right next to a lake. It wasn't a large one, but it was plenty large enough to let their amphibian instincts relax and enjoy the wet environment.
Beru looked over to Ganma and Inko and noticed they were still taking there time setting up the tents. Inko was paying rapt attention, taking notes in a little notebook.
She decided to take Izuku and Tsuyu on a walk around the lake, holding their hands to make sure they didn't wander off.
It was a rather peaceful walk. It had been a while since her and Ganma had been able to come out here, what with their work and Tsuyu's birth.
Izuku was the one to break the silence first. "U-um…"
Beru looked down to him. "Yes, Izuku?"
He looked anxiously excited. She was curious if she would ask about their quirks. After all, even for mutation quirks they looked quite strange. She was right, but not for the reasons she thought he would ask.
"Sorry if this is r-rude, but d-do you all have frog mutations? You s-seem to have some similarities to them. The wider mouths and wide eyes seem like frogs. Ganma seems a little different, maybe a toad? Can you extend your tongues out, stick to walls? Oh! Can you shoot poison from your stomachs? Imagine how useful that would be for a hero. Paralizeavillainwhilehidingonawalltotakeoutavillain…"
Izuku continued into his mumble storm. While Beru looked down at him bemusedly, she really wondered how he spoke that much without taking a breath, Tsuyu looked at him with curiosity.
Her tongue stuck out a bit, a finger going to her cheek. Deep in thought, she wondered. "A hero huh…?"
Beru took a few moments to think over his fast word jumble and formulate a response. She shook his hand to get his attention. "Izuku, please take some breaths, I'm afraid you might be running low on air with how long you've been going for."
Izuku seemed to snap awake then, practically gasping for breath.
After a brief chuckle, she did her best to answer his questions. "You are right, kero, Tsuyu and I have quirks called Frog, while Ganma's is called Toad. The descriptions are that we can do whatever a frog or toad can do, kero, but honestly, we aren't very inclined to fighting or hero work so we never really tried to find out all that we can do."
Izuku seemed disappointed so she decided to play a little prank on him to draw his attention back.
She let her tongue dangle from her mouth, and with a flex, poked him in the cheek with it.
This startled Izuku, but when he realized what had touched his cheek his eyes lit up and an almost blinding smile bloomed onto his face. "Was that your tongue?!"
"Yes, we can extend our tongues. I myself can stick to surfaces, but I haven't really trained to hold myself up for very long. Ganma can't stick to surfaces, however."
"That's so cool! Even if you didn't use it for hero work, I wonder what you could do in your day to day. Using your tongue to grab things, sticking to walls, even if for a little bit, to clean hard spots to get to."
Beru smiled. She had in fact used her quirk to make her chores at home easier. Before she could respond to him, she heard Tsuyu speak up for the first time.
"You've been asking about our quirks, ribbit. What's yours?"
Izuku seemed to shrink in on himself a bit, but still held some of his excitement over quirks. "M-mine is called Wolf. I-it lets me change into a w-wolf and have stronger senses while unchanged. My wolf form is a bit big, though. It can be a little scary…"
"Can we see it?" she asked, finger on her cheek.
With red cheeks, having nothing to do with how cute she looked, no sir, he turned to face away. "I-I don't know, I don't want to scare anyone…"
Bery noticed how uncomfortable he seemed and decided to interject. "Tsuyu, kero, let's get back to camp. It's getting a bit late, and I want to get started on dinner."
Tsuyu looked between her mother and Izuku. She really wanted to see what he looked like, but something in Beru's tone told her to drop it. "Ok…"
Izuku heard her and felt guilty. She seemed a bit sad being unable to see his wolf form. "Maybe… Maybe I can show you later?"
Izuku could have sworn his mind was playing a trick on him, but he thought he saw her lips quirk up a bit, seeming like a small smile. She just let out a ribbit as they walked back to camp.
The two families had just finished eating dinner when Izuku decided to rip the band-aid off
"M-mom?"
"Yes, sweetie?" Inko looked down to him.
He looked up into her with a nervous but resolute stare. "I-I want to show them. Asui asked if she could see, and I want to show them."
Inko was concerned. She was proud that he was willing to show his wolf form after what happened at the park but was worried he was pushing himself.
"Are you sure, Izuku? You don't have to if you don't want to."
"I-I want to." Izuku waves his arms around him. "They're doing all this for us. I want them to know."
Inko lets out a breath. "Alright, if you're sure. Apologies in advance, Beru, Ganma, Tsuyu. His form is a little…big."
Before any of them could respond, a flash of light lit up their campsite. When they looked over at the light, they were stunned by the sight before them.
Most transformation quirks that turned a person into an animal tended towards the animal form being of equivalent age, in animal years. They had believed that his transformation would show a small pup of perhaps a month or 2 old.
What instead stood before them was what could be mistaken as a fully grown wolf. 2.5 feet at the shoulder and 6 feet long from snout to tail. The biggest standout, surprisingly, was its face. The face of a puppy stood out from the rest of the large animal's body.
While Inko herself found this look to be absolutely adorable(I mean, look at those giant squeezable cheeks!), she knew how it could appear to those with mutation quirks holding prey instincts.
Her fears were realized when she looked over to the Asuis. Ganma was breathing heavily, his throat noticeably inflating, whether that was from him readying an attack or trying to look threatening she wasn't sure. Beru had moved so that she was standing primarily in front of Tsuyu to protect her.
Young Tsuyu's reaction worried her the worst, however. She was frozen stock still. So still she was worried the girl wasn't breathing. The only indication she was still aware was the slight shiver she was under.
It was obvious that Izuku had noticed this as well. He had lowered his head, body curling in on itself. Some might see it as a predator preparing to pounce, but she felt she knew her son enough to know he was preparing to cry, afraid he had scared them too.
It was then she decided that drastic measures were required.
While they were packing for the trip, she had noticed he held prolonged attention on a certain item. An item she hadn't originally been planning to take with them, as she was her young boy could hate her for even considering using.
She reached towards her purse and pulled out the item with all the gravitas of a woman knowing she was condemning her son t a horrible fate.
She pulled out this item, and squeezed.
*SQUEAK*
Izuku's head immediately snapped towards her, ears standing on end. His full attention on the item she held in her hand.
A green tennis ball.
He stood at attention, tail wagging ferociously. She waved her hand back and forth, his attention never leaving the ball. He had just started panting, getting excited at the existence of the odd item, when Inko threw it.
He ran, desperately trying to catch it before he lost site of it. So focused was he that he barely paid notice to the bush he tripped over, scrambling back to his feet to chase the ball.
Inko was giggling to herself, watching the Asui's dumbfounded expressions, when he ran up to her panting and holding the ball in her mouth.
It was on the third return trip that the two Midoriya's heard the giggling interspersed by ribbiting coming from the Asui mother and daughter.
It took a bit for the giggling to wind down when the young girl Tsuyu noticed the wolf crouched before her. He had just dropped the ball before her with a large dopy smile on his doggy face, tail wagging a mile a minute.
She tentatively reached out to grab the ball, almost afraid he might snatch it from her. After he let her pick it up, she threw it as far as she could. Which, unfortunately, wasn't very far considering how small she was.
She was frustrated. That throw didn't give the giant puppy the run he clearly craved.
She sat there, finger on her cheek with her tongue sticking out of her mouth, thinking about how she could throw it better when an idea struck.
Izuku was just returning from Beru taking a turn at throwing the ball when something snatched the ball from him. He let out a yip as he looked towards the thief.
He saw Tsuyu standing on the ground in what must have been a proud pose. Her tongue was dangling out of her mouth with the ball attached to the tip of her tongue.
Before he could move to get the ball back, she started spinning. Once, then twice. Her tongue trailing out. At the third spin she launched her tongue out, releasing the ball.
This got the desired effect of launching the ball pretty hard, giving Izuku a good run to get it. Unfortunately, Tsuyu didn't have good aim considering how young she was.
This led to the ball being fired into the lake nearby. Everyone stared, shocked at how hard she launched the ball before they heard a panicked shout laced with horror.
"IZUKU, NO!"
It took a moment, but dawning horror finally registered upon the adult Asuis. They had been enjoying the canine chasing the ball, not focusing too much on where the ball was thrown. The lake didn't seem like an issue at first. After all, most full-grown dogs could swim. They had forgotten an important fact.
While the canine seemed large enough to be full grown, the person behind the lupine face was still a five-year-old.
A five-year-old that could not swim. Especially not in a form he had just started getting used to.
Everyone watched in horror as Izuku took a running leap at the ball in the water.
Izuku had been so focused on chasing the ball, enjoying how much fun everyone was having, that he didn't notice where the ball had landed. His instincts told him to chase, so he chased it. It wasn't until he had grabbed the ball that he came back to himself, realizing where he was.
He started to panic.
Inko bolted out of her chair, releasing a scream when a large blur leaped towards the lake.
Ganma splashed into shallower part of the lake and shot his tongue out to the flailing pup. As it wrapped around him he started panicking even more. Trying to scratch at and bite what had grabbed him, Ganma struggled to pull him out without getting hurt.
Izuku was dropped next to the fire. Before he could snap at whatever had grabbed him, he felt a pair of arms wrap a towel around him. A familiar voice letting out a panicked, "MY BABY!"
He froze, glancing behind him to see his crying mother, Inko, desperately trying to dry him off.
"Izuku I know you my have high tension right now, but I need you to calm down and transform back so I cangetyouintodryclothesoryoumightgetsi-"
Her worried rambling was cut off by a loud "CROAK".
"Mrs. Midoriya, please take some deep breaths. You will be unable to calm his panicking down if you yourself are panicking, croak." A wet Ganma had leaned down. Holding a hand to her shoulder in a show of support.
Inko looked down on her shivering son. He was whimpering softly with his tail between his legs. She took a deep breath.
She continued to attempt to dry his fur, trying to impart calm in the rubbing of the towel.
"Izuku, sweetheart, can you change back? I'll finish drying you off and get you into a dry set of clothes if the ones you're wearing are wet." She continued to dry him off, knowing it wouldn't really do much with how much fur he had.
With a flash of light Izuku was sitting there. Before Inko could wrap his smaller form in the towel, he leaped at her, hugging her desperately.
She did her best to wrap his sobbing form in the towel and lifted him up and sat a little closer to the fire to dry him off faster. She started rubbing his head continuously whispering that he would be ok. Why? Because mommy was here.
It took a little while for him to calm enough for her to bring him into their tent to finish drying him off and change into dry clothes.
She was still carrying him, his head buried in her shoulder when she walked up to the larger Asui and bowed. "Thank you so much for diving in to save him! I don't know what I would've done if he…"
Ganma looked up to her and showed a small smile, still drying his hair. "Don't worry about it. I just did what I would've done if my little girl were in the same situation. Is he doing alright?"
"Yes. He's still shaken up, but he's doing a lot better. Izuku, can you please thank him?"
Izuku turned head so that one eye was peeking out. "T-thank you Mr. G-ganma." His thanks given, he turned his head back into his mother's shoulder.
The two adults smiled at this. Inko glances around. "Where are Beru and Tsuyu? Is Tsuyu alright?"
Ganma sighed and dropped his towel into his lap. "Tsuyu is pretty shaken up. She feels guilty for throwing the ball into the lake. She ran into our tent after you entered yours. Beru is with her."
Neither notice Izuku glancing toward the tent. It only having just occurred to him how Tsuyu must be feeling. He looked away from the tent only to see something on the ground, and an idea popped into his head.
Izuku started fussing, wanting to be put down. Inko put him on the ground confused. She he would want to be held for longer.
Then she saw what he was going to get. The tennis ball. "I was sure he had lost it in the lake… Did he keep a hold of it even when he was struggling and almost drowning?"
He picked up the ball and walked towards the tent the two Asui's were in.
He took a few moments to think before he spoke up hesitantly.
"A-asui, are you in there? Are you ok?"
After a few seconds of silence, the zipper to the tent opened enough for Beru to poke her head out. "Sorry Izuku, she needs a little bit. Her emotions are running a little high right now. She feels pretty bad about throwing the ball into the lake."
"O-oh, um. I-It's not her fault. I was having a lot of fun u-until…" He looks down, seeing the ball in his hand again. "Can you tell her that, that it was fun? Can you also give her this?"
Beru looked down at his outstretched hand. Her eyes widened when she saw the tennis ball her daughter had thrown.
Izuku smiled up to her. "I held onto it the whole time! I want her to have it."
Beru smiled at this. Even when he had almost drowned, he was worried about her daughter. "One moment." She dipped her head back into the tent.
The tent flap opened fully a few moments later. Tsuyu was sitting in her mother's lap, face leaning into Beru's stomach.
She turned her head so that he could see her face. She had clear signs of having cried.
Before Izuku could speak he heard Tsuyu let out a sad little "ribbit".
"I-I'm sorry…"
Izuku rocked back, surprised. "Sorry? What for?"
"If I hadn't thrown the ball, y-you wouldn't have almost…" Her eyes started watering, about to let out more tears.
"I-it's not your fault, it was the best chase all night! A-and besides, I want to be a hero! A little water won't stop someone like All Might, so it won't stop me!" Izuku puffed his chest out, giving his best impression of All Might's smile.
The goofy look made Tsuyu smile, letting out a giggle.
Izuku reached his hand out. "Here, I want you to have this. Can we play ball again sometime? Maybe we can practice to help you throw better!"
Tsuyu reached out and takes the ball.
"It's not much, but I hope you feel better. It's the first ball I've played with as a wolf, so don't lose it!" Izuku let's out another bright smile.
Inko decided then was a good time to call it a night. "Izuku, it's getting late. How about we go to bed and let her relax."
"Ok mom! Goodnight Asui, Mrs. Asui." He waves to them as he walks to his mom.
Beru bid him goodnight with Tsuyu letting out a small "night".
As everyone settled into bed, Tsuyu cuddled in between her parents. She held onto that ball. She wasn't sure why. It was just a ball, after all. But then she remembered his smile. She slept with a smile on her face.
The next morning saw the families taking a hike through the forest. As most heroes don't patrol these woods very often, they let Izuku use his quirk to burn off energy as a wolf.
Tsuyu was watching his latest bout of zoomies, being carried by Ganma while she rested from a long portion of the walk, when a thought crossed her mind. "What would be like to ride him while he runs?"
She decided that it was probably rude to ask. Who just asks someone if you could ride them?
Inko was enjoying a lovely conversation about what it was like raising their children when she noticed Tsuyu constantly look at her son while he was running around.
She had a hunch what she was thinking about and decided to act on it. "Hey Tsuyu?" When she looked over at Inko, she dove right into it: "Would you like to ride on his back while we hike?"
Tsuyu's eyes widened. Hesitantly she responded. "I-if he's ok with it…"
Inko smiled to the little girl. "Izuku, sweety! Would you come here a moment."
Izuku stopped running, head snapping in her direction as she spoke. He ran up to them, tail wagging furiously and tongue waggling out in a huge doggy grin.
Inko smiled at him, giving his head pets and scratches behind his ears. "Izuku, would you be willing to give Tsuyu ride?"
Izuku's wolf eyes widened at that prospect. He quickly turned towards Tsuyu and started bouncing up and down, letting out excited yips and barks.
Tsuyu stared down on him with wide eyes as he circled several times before with his side to her and Ganma. He looked to her with excitement.
She looked up to her father with a ribbit to make sure it was ok.
Beru was the one to show concern for Tsuyu's safety. "Are you sure it's safe? There's no harness to keep her on him. What if she falls off?"
Izuku's ears pointed back, and he stared down at the ground in thought. Inko was about to assure her that Izuku would be careful, but Izuku perked up and looked Beru in the eyes.
Continuing eye contact, he started trotting around, purposefully not running around.
Inko caught on quickly, "See, Izuku won't be running around. She'll be safe. She should just hold onto his fur tight. I'm certain he won't let her fall."
Beru looked between her, Izuku, and Tsuyu. Ganma added his own opinion. "Let's let her have some fun." He smiled to his wife, "After all, it's not every day we can get the chance to ride a wolf around a forest! I'm confident we can catch her with our tongues if she does fall."
Ganma shot hit tongue out to a nearby tree to prove his point of their speed.
Beru hesitated a bit more before assenting.
Izuku ran back up to Ganma. He looked up to Tsuyu, waiting for her to be put on his back.
Tsuyu had a moment of worry, grabbing large tufts of Izuku's fur, worried she would fall off. Izuku felt no such concern and started trotting forward, letting her get used to riding on wolf back.
She tensed as Izuku started walking. She slowly began to relax the longer they walked for. She found she was even having fun.
Izuku looked back at her, and seeing her smiling, he began to pick up speed to a trot.
The little girl let out a ribbiting giggle as he sped up. "Faster, ribbit, faster!"
Izuku ran around, heeding her request. He ran down the trail, around their parents, between the trees. The two of them were having so much fun, they didn't notice something wrap around Izuku's torso until he was lifted into the air.
"Croak. Remember what we agreed on. No running at full speed." Ganma admonished them while reeling them in with his tongue. "Especially between the trees where we can't see you."
Properly chastised, the two kids went back to running around. Staying slow and in site of the adults. Even slower, they still enjoyed the experience.
A while later they headed back to their camp site, Izuku panting heavily and Tsuyu laying limply across his back. Holding on for so long was exhausting for a child.
The rest of the trip went much the same. Izuku running around with Tsuyu on his back, some fishing, and more.
They had even taken some time to teach the kids how to swim properly. Tsuyu took to it like a frog to water while Izuku was very proficient in the "doggy paddle".
At one point Izuku, in his wolf form, had stood in shallow enough water that just his back was above water. Tsuyu sat upon his back like a giant furry lily pad.
The kids were sad when they had to pack up the campsite and head home.
"Mom, when will we be able to do this again?" Izuku was standing near Inko as she helped the Asui's load the car they used to get there.
"I'm not sure sweety. We'll try to do it as much as we can, but I only get so much time off from work. Not to mention how far away we live from here it will be difficult to do this a lot." Inko was busy stuffing a rolled-up tent on top of all the suitcases, so she didn't notice Izuku's eyes start tearing up, but she did hear it in his voice when he spoke his next question.
"D-does that mean we w-won't see the Asuis again?"
Inko crouched down and pulled him into a hug. "Of course we will Izuku. We already promised we'd be going camping again. Besides, we have their phone number. We can call them whenever we want."
"Ok…"
She could tell he wasn't entirely satisfied with that answer. Sure, they wouldn't be able to see each other every day, or even every week, but they would still see each other again. It's not like she's his only friend. He still has Katsuki and the other kids from school.
Now that she had thought about it, it had been a while since he visited. He only ever visited when Mitsuki wanted to visit instead of visiting to talk about heroes with Izuku. "When did that change happen?"
The drive back was peaceful. The kids were huddled in the back seat with Inko, watching videos about heroes on her phone. Inko did not squeal inside, thinking about how cute they looked, no sirree.
She squealed on the outside, thank you very much.
The separation at the Asui home held many tears. The 2 children hugged, promising they'd speak when they could. Inko cried, watching two children being absolutely adorable.
When they left Inko promised they would call once they got home to let them know they made it safely. Izuku and Tsuyu spent a few hours talking about childish nonsense until the whole vacation caught up to him and he fell asleep.
The next several years went like this. The Midoriya's visiting for a camping trip. Sometimes just visiting. Inko was even able to babysit Tsuyu one summer while the Asui's went out of town for work.
Izuku and Tsuyu talked as often as they could. About Heroes, about quirks, about becoming heroes. Izuku had even written a notebook detailing how her quirk could help her as a hero.
When two were 8 years old The Asuis had their second child. A son named Samidare. Their second daughter was born 4 years later, named Satsuki.
Inko helped them when she could. Helping take care of them when they were small during their rare visits, babysitting during the summer, etc.
There was discussion at one point about either of the families moving closer to each other, but their jobs made it too difficult. The Asui's managing to secure their own legal practice in Aichi prefecture and Inko's practice being where it was made it difficult to move. On top of that, one of the most prestigious, of not the most prestigious, hero schools were located near them.
U.A. University. Haling to be the best school in the country. It was also the same school All Might himself graduated from. If there was ever a hero school Izuku wanted to go to, it was this one. After, what kind of All Might fanboy wouldn't want to go to the same school he graduated from.
Katsuki started distancing himself from them to Inko's disappointment. She knew that he and Izuku were best friends when they were younger, but something seemed to happen around the time that Izuku got his quirk that had Katsuki riled up.
She knew he would be a bit of a firecracker when he grew up. After all, his mother was Mitsuki Bakugou. She wasn't just a firecracker; she was the whole fireworks stand. Even with that though, his pulling away from the Midoriyas seemed odd to her. No one could figure out why. Anytime someone would ask, he would respond with "The future number one hero doesn't need any extras riding his coattails" or some such.
Inko was just glad they had met the Asuis. She wasn't sure what her son would do if he didn't have Tsuyu as his friend. He never brought any other friends over to visit after Katsuki stopped visiting. She was starting to worry that he may not have other friends but decided not to pry.
Surely he had other friends. Who wouldn't want to be friends with her sweet boy.
She was wondering when the girl would confess her feelings to her son. While she was rather blunt, a habit she picked up to help people understand her since her face wasn't as expressive as most people's, her son tended to be rather dense when it came to romance. Not even the heart shaped chocolate that she gave him when they were 14 clued him in. It even had the most adorable frog face in the center of it for crying out loud!
Life continued on, the Midoriyas having found a happy pattern after meeting the Asuis. Izuku was happy, he was doing great in school. He was even working out to be ready for his run at being a hero.
This all took a rather severe turn one day, when Izuku, at 16, was coming home from school.