Hello all Storm here with a new story! Here we'll be seeing an interesting idea, I won't spoil anything but I hope you all enjoy the story. So, without further ado.

I own nothing

Quirks, formerly known as Meta Abilities, are unique powers possessed by people, granting them superhuman abilities from being able to manipulate an element to possessing super strength. No one knows how Quirks came to exist, some theorizing they're the next step in human evolution or were spread by an unknown virus carried by mice. All that is known is they've existed for over a hundred years, since the first incident of a newborn baby in Qing Qing City, China.

Though as more and more people developed Quirks, chaos and unrest ensued as criminals also began gaining Quirks, allowing them to commit more crimes and remain free with their new powers. This leading to ordinary civilians to take matters into their own hands, giving rise to the first "Heroes" as Vigilantes, starting the Vigilante Era.

But over time, order soon began being restored as Quirk Restriction Laws were soon put into place with the new superhuman society. While Pro-Heroes soon began appearing, Quirk-users that worked alongside law enforcement to help defeat the ever appearing Villains. Which also caused the Vigilantes to start disappearing, with them no longer being needed with the rise of Heroes.

While in Japan, Pro-Heroes were officially ranked based on numerous factors, such as the level of strength they've displayed, the number of cases they've solved, their general popularity, and their overall contribution to society. With the current Number One Hero being All Might, seen as the world's greatest Hero and known as the Symbol of Peace. With him having managed to bring Japan's crime rate down below six percent since making his debut.

While the Number Two Hero was known as the Flame Hero: Endeavor, with his real name being Enji Todoroki. Having risen to become the Number Two Hero when he was only twenty-years-old, though desired to become the Top Hero and strongest. Only to be unable to surpass the popular All Might, with Endeavor being forced to admit that the gap between them was too great to close.

But while Endeavor knew that he may not be able to surpass All Might, he could create a Hero to achieve his goal in his place. And what better Hero to place his ambitions on, than a child born from him and inherited his power. Along with their mother's own Quirk, combining together to create one giving them power over fire and ice.

Which is for that reason, Endeavor married Rei Himura in a Quirk Marriage due to her Ice Quirk being able to counter the drawbacks of his Hellflame Quirk. Though despite his reasons for marrying her, Endeavor would admit he had some feelings for Rei, seeing she was a strong person.

With their first children having been born prematurely three years ago, twins in the form of a boy and a girl. Both of them having the same crimson hair and turquoise eyes as their father, while they named the boy Toya and the girl Naruko.

And after three years, both Naruko and Toya have already awakened their Quirks, but rather than having the Quirks that Enji had hoped they would have, they both instead inherited Fire Quirks. Only they were different from his Hellflame, with Toya's flames being even stronger and hotter than his own. While Naruko's flames were unique, not only with them being a light blue color, they were instead ice flames, so rather than making them hotter she makes them colder.

Though despite neither of the twins having the Quirk he desired them to have, both of them still had incredibly powerful Quirks that were stronger than his own. So, Enji was sure they'd be able to surpass All Might one day and decided to place his ambitions on them. Along with him and Rei having another daughter a year after Naruko and Toya were born, naming her Fuyumi.

Currently, Enji was training both Naruko and Toya in the training room in their family's home. With Toya wearing black shorts and a white, short-sleeved hoodie, and Naruko wearing black shorts and a light blue shirt, along with having her long crimson hair done up in pigtails.

"Focus, both of you! Quirks like ours are more dangerous than others, that if you aren't careful you'll lose control of your flames, even yours can be dangerous Naruko, if you end up freezing everything around you. But also make sure you don't hold back from turning up the heat, Toya, otherwise they won't be hot enough to take down any Villain." Enji instructed, as both children nodded while smiling as they shot off blasts of fire.

"Right Tou-san! But when are you gonna teach me to use Prominence Burn?!" Toya asked eager to learn his father's signature move, wanting to see how powerful it'd be when he uses his own flames.

"Hey! We're both gonna learn Prominence Burn, not just you!" Said Naruko, looking at her brother in annoyance that he only included himself.

"No way, your flames only make things colder, while mine are like Tou-san's and will burn away any Villains." Said Toya while smirking at his sister, only to get a layer of frost on his face when she shot a fireball at him.

"Yeah, I can make things colder. It helps when you need to cooldown, hothead." Naruko replied with her own smirk, with Toya giving her an annoyed look while the frost evaporated.

"Enough, both of you. And you'll both get the chance to learn my attacks when you're older and have more control over your Quirks. For now though, you'll be learning to make sure you have control and that they're hot or cold enough." Enji said, stopping before they could end up fighting, the twins nodding as they resumed their training.

*Timeskip-Three Months*

Three months passed by as Enji continued training Naruko and Toya to use their Quirks, with both of them being eager to learn everything he had to teach. With both children having their own ambitions lit by their father to surpass All Might and become the strongest Pro-Heroes in the world.

Though it did sometimes lead to them bickering about which of them would be the Number One Hero, neither of them willing to share the title nor wanting to be Number Two.

But one day, when they were about to start training again, Enji noticed part of Toya's hair was starting to turn white. Something that Toya tried passing off as nothing and instead tried getting back to training, only for their father to noticed that he actually had burns on his arms. Which only started getting worse the longer his flames were activated, causing Enji to end the training for the day before he and Rei took the twins to the hospital to make sure they were alright.

With both Enji and Rei sitting in a doctor's office, waiting to see what the problem was, the parents looking up when the door opened and the doctor entered.

"What happened? Why was Toya covered in burns?" Questioned Enji immediately, knowing he should have also inherited his resistance to high temperatures, which should be even better to go with his stronger Fire Quirk.

So it's worrying how Toya could have burns, when it should be impossible unless they came from flames stronger than he could handle.

"After running some tests on young Toya's Quirk, it seems that while he has a Fire Quirk much stronger than your own, he doesn't have the same resistance to scorching heats. Instead, Toya has inherited your resistance to freezing colds. Meaning that every time he uses his Quirk, he'll run the risk of burning himself, if he isn't careful. So, he'll need to minimize how long he creates his flames to safely use his Quirk, or else he could end up causing permanent damage to his body." The doctor said, looking at the parents, who were concerned to hear this that Toya's Quirk could end up hurting him.

"And what about Naruko? Could her Quirk end up giving her frostbite or freezing her if she overuses it?" Rei asked in concern and worry for her daughter, since if Toya's Quirk could burn him, then could Naruko's Quirk end up freezing her.

"That is where I have some good news. We've run the same tests on young Naruko and her Ice Fire Quirk, learning she also inherited your resistance to cold temperatures. And due to the nature of her Quirk, it was also enhanced by your Hellflame Quirk, making it so she's not only has a stronger resistance to the cold; but allows Naruko to regulate her body temperature. So, there's almost no worry of her freezing herself from overusing her Quirk. And once she's had proper training to master it, along with a Hero Costume made to suit her Quirk, the side effects she does suffer from would be non-existent at that point." Replied the doctor, much to their relief that Naruko wasn't in any danger as well.

Though Enji frowned, since while it's good that Naruko's Quirk won't hurt her. Toya, however, can't use his for extended periods of time, meaning it's unlikely he'll ever be able to become a Pro-Hero, let alone be able to surpass All Might.

'Meaning only Naruko can be trained now.' Thought Enji, seeing Toya as a failure with the weakness of his own Quirk, and only Naruko will be trained from now on.

*Timeskip-One Week*

After returning home from the hospital, Enji told Toya that he wouldn't be receiving training anymore due to him being burned by his Quirk, something the boy had protested against. Even more so, after learning that Naruko would still be trained since she's able to resist the freezing temperatures her Quirk produces. Something that made Toya jealous and resentful of his sister, that just because she isn't hurt by her Quirk, she's still being trained while he's cast aside.

"It's not fair! Why do you still get to be trained, but not me?! So what if my flames hurt me, I can handle the pain and the burns! It'll just push me to be stronger to resist the heat!" Said Toya to Naruko and their little sister Fuyumi, who had the same white hair and grey eyes as their mother, though with flecks of crimson.

"Uh, Toya, wouldn't it still be dangerous for you? You could still get hurt if you use too much of your flames." Fuyumi said, worried for her older brother and that he could hurt himself, if he isn't careful.

"Yeah, we don't want to see you get hurt Toya. And neither does Tou-san and Kaa-san, they're just worried and want to make sure you're safe." Said Naruko, also worried for her brother.

Only for their words to offend Toya, as he scowled at them.

"What do either of you know?! You're both just girls anyway!" Toya retorted, only to yelp when Naruko pulled on his ear and gave him an unamused look.

"Well this girl is still older than you buddy." Naruko said, annoyed at his comment.

"Only by a minute." Muttered Toya before wincing when she pulled his ear again.

"That still makes me older. Besides, I know what you're feeling, since Tou-san lit a fire in me too, so I want to surpass All Might just as much as you do. If our positions were reversed, I'd be just as heartbroken and lost as you are, at suddenly losing my goal and dream." Naruko said, letting go of her brother, understanding what he's feeling since she'd feel the same if their positions were reversed.

"Besides, despite what Tou-san said, I still believe you can be a great Hero. Especially since, from what I've heard from Tou-san, Support Companies have been making great progress in developing Support Items and Hero Costumes. So, I'm sure they'll be able to make something you can use to still be able to use your Quirk without worry." Said Naruko, smiling at her brother, believing he can still be a Pro-Hero, he'd just need the right costume and Support Items to help him with his Quirk.

"You think I can only be a Hero because of a costume and items?! I don't need anything to prove I'll be a great Hero! I can become stronger on my own!" Toya retorted, angry and believing that Naruko was pitying him, thinking he needed help to be a Hero.

"That's not-" Naruko said while frowning, only for Toya to storm off, not wanting to hear any excuses she has.

While planning to show her, their father, and anyone else who'd doubt him that he can be a Pro-Hero, even if he has to train on his own to do it.

*With Enji*

Meanwhile, Enji was downstairs watching the news, which was showcasing another one of the Symbol of Peaces heroics. Grinning and smiling like a fool, while waving and laughing afterwards at the gathered crowd only infuriating Enji. Or further infuriating him, due to Toya's refusal to give up on not being trained anymore, having been annoying Enji constantly at his son's refusal to give up.

'Of all the things he had to inherit, why did it have to be my stubbornness?!' Enji thought, knowing Toya got his stubbornness, making it impossible for him to quit on surpassing All Might, unless they found something else to put his attention on.

"I just saw Toya after he talked with his sisters. He looked upset." Said Rei, entering the room and getting Enji's attention, with the Hero only grunting in annoyance.

"He'll learn to accept it and give up, when he finally sees I'm not changing my mind. Whether he likes it or not." Enji stated, making the woman frown as she doubted that would happen.

"I'm also planning to advance Naruko's training, she's already gotten a good enough control on her Quirk, now she needs to start learning to use it in combat. And Toya will forget about wanting to be trained eventually, and instead spend time with his siblings." Added Enji, since they planned to have more children, so Toya doesn't get lonely while Naruko's busy training.

"Doesn't that seem cruel to Toya? How do you think he'll see Naruko's training and us having more children? They both already know what you want to achieve through them, it'd only hurt him more and feel like he's being replaced." Rei said, since while she'd like to have more children, she didn't want Toya to interpret it as him being replaced, rather than making sure he isn't lonely.

"It's the best way to make sure he gives up on his ambitions. By showing him that Naruko will carry on, while he'll have his time taken up with more siblings to keep him busy." Enji replied before getting up to inform Naruko that her training will be picking up.

*Timeskip-Six Years*

Six years have passed since Toya stopped receiving training from his father and was deemed a failure, due to him being unable to use his Quirk for extended periods of time without burning himself. With Enji and Rei having had two more sons, Natsuo, who was born four years after Naruko and Toya, and their youngest, Shoto, who was born eight years after the twins. And it was with Shoto that Enji finally had the child he'd wanted, one who possessed the combination of his and Rei's Quirks, given his dual colored hair and eyes.

Which only furthered Enji's obsession to surpass All Might, at now having two children with the power to become the Number One Hero. Naruko with her Ice Fire Quirk and now Shoto with his Half-Cold Half-Hot Quirk. With this obsession soon giving way to hatred and tunnel vision, as he focused only on ensuring they'd have the power to beat All Might, not matter what. While this only drove Toya further into despair, seeing his father now focusing on not just his sister, but now his youngest brother as well.

While Naruko and Toya's relationship further deteriorated, with his envy and resentment growing each time he saw her training with their father. Along with believing that Naruko is still pitying him when she's tried offering to help him find ways to use his Quirk. Leading to Toya now being openly antagonistic to her, while ignoring the fact that her training with their father has grown more brutal over the years, to the point she could barely move afterwards.

With things soon reaching their breaking point, when Shoto began showing signs of awakening his Quirk, despite only being a year old. Toya knowing what that would mean, given the power and potential his Quirk would possess.

Leading to an argument between Toya and Enji, after the latter ordered his son to stop training in secret, given he'd still be covered in burns sometimes. Only for Toya to refuse, with their argument drawing the attention of Naruko, Natsu, Fuyumi, and Rei, who was carrying the infant Shoto.

"I can't give up! I can never give up because I have you as a father! You were the one that gave me the desire to surpass All Might and now you want to take that away from me! No matter what you do, my fire will never go out, Endeavor!" Said Toya, looking at his father with tear-filled eyes, before they noticed the rest of their family had shown, with Toya's soon falling on Shoto in his mother's arms, before seeing his father was looking at him as well.

"LOOK AT ME!" Toya shouted at his father, before to the horror of his mother and siblings he ran at Rei with a flame-covered hand intent to attack Shoto.

"Toya!" Yelled Naruko in horror that he'd actually try to kill Shoto.

Thankfully, before Toya could actually injure anyone, Enji grabbed his arm and snuffed out his flames, looking at his son in anger. With Naruko, Fuyumi, Natsuo, Rei, and Shoto all being horrified at what Toya tried doing. Shoto especially, being able to tell that his older brother actually tried to kill him just now.

"Enough Toya! I tried being kind before in getting you to stop, but now I'm telling you! You will no longer train yourself, anymore!" Enji shouted, angered that Toya would actually try to do that, with Toya yanking his arm free.

"What the hell is wrong with you?!" Demanded Naruko, glaring at her twin, not believing he'd actually try attacking Shoto.

"Stay out of this!" Toya retorted while glaring at her.

"Hell no! I don't care if you're angry, you just tried to kill Shoto, our little brother! And why, just because of the Quirk he was born with?! You can be angry at me, Tou-san, and anyone else if you want, but don't take it out on our younger siblings!" Shouted Naruko, refusing to let Toya attack their siblings, just because of his anger towards their father and her.

"Fine, I'll take it out on you!" Toya yelled before punching Naruko across the face, sending her flying across the room, much to the shock of Naruko and the rest of their family that he actually physically attacked her.

"You…you actually hit me?" Naruko said looking at him with wide eyes before Toya charged her with flames emitting from his body.

Something that shocked and horrified Naruko, that her brother just really hit her, since he'd only ever been verbally antagonistic towards her. And now he was willing to use his Quirk against her as well.

With it only being thanks to her training that Naruko was able to activate her own Quirk and fire a blast of cold flames at Toya. Sending flying away from her and through one of the doors going outside into the garden.

Toya grunting as he hit the ground, before getting back up and glaring at his sister, before shouting and firing a large blast of flames at her. Which Naruto countered with a blast of ice fire, the two attacks colliding against each other. The two attacked swirling together before triggering an explosion, with Toya jumping through the smoke and throwing his flame-covered fist at Naruko. Who deflected the punch, sending her brother flying back with a fireball.

Only for Toya to land on the ground and began gathering up a large amount of flames around him.

"Prominence Burn!" Toya yelled before firing a concentrated beam of flames at Naruko, having managed to recreate his father's attack, only it wasn't as strong as Enji's.

With Naruko quickly forming a wall of ice fire in front of her, with it being strong enough to stop Toya's attack from hitting her.

"I thought you would have learned; fire always beats ice!" Shouted Toya as he increased the heat of his flames to push through Naruko's, while ignoring the pain as he was being burned by them.

"And you should learn, experience will beat power!" Naruko retorted, before firing a concentrated blast of ice fire that shot straight through Toya's Prominence Burn and impacted her brother, with Toya crying out the sudden extreme cold and ice forming on his body.

Before she then fired more of her flames at Toya's to make sure they don't spread, Naruko approached her brother, ready in case he tried attacking again.

But when she reached him, Naruko was horrified to see most of his clothes had been burned away, revealing the burns covering his body from using his Quirk, along with the encroaching frostbite from her own attacks.

"T-Toya! I-I'm sorry, I-" Naruko said, running over to try and help him with her Quirk and cool him down, along with soothing his burns.

Only for Toya to smack her away before she could try, while giving her a look of pure rage and hatred.

"Don't ever try helping me! I never asked for your help, and I never will! I don't need you or anyone trying to help me, I'll show all of you that I will be the strongest!" Shouted Toya before getting up and storming out of the house, heading straight for Sekoto Peak, where his father once trained.

Knowing that's where he'll gain the same strength and power, only he'll be even stronger, and then his father will finally have to acknowledge him and his strength.

With Naruko watching him go with a saddened expression, wanting to go after Toya and help him, but knowing he'll only push her away.

*Timeskip-Sixteen Years*

Naruko opened her eyes as she came out of her memories.

'That day, why couldn't have I actually tried helping Toya?' Naruko thought, have always regretted that day, not only for hurting her brother, but it was after that that Toya had completely cut her out of his life.

Never talking to her, interacting with her, he barely even acknowledged her presence. And nothing she ever said or did changed anything.

'Could I have done something different? Even if you hated me, would I have still been able to help you, if I tried harder? If I did, would you still be here?' Naruko thought sadly, wondering if she'd done something different, would Toya still be here, with both of them having achieved their dream of becoming Pro-Heroes.

Knowing it hadn't been long after, that their mother was admitted into a hospitals psychiatric ward, after she nearly burned Shoto due to the recent abuse from their father. And it wasn't long after that, that Toya had died after burning himself to death from his own Quirk, the only thing left being a fragment of his jawbone.

'If you were here, I probably wouldn't have gotten these.' Thought Naruko, tracing the three faint scars that now lined her cheeks in the shape of whiskers, while shuddering at remembering how she got them and who gave them to her.

Though suddenly, Naruko was pulled from her thoughts at the sound of an explosion, with the redhead looking and seeing the explosion was close to where she was.

'No time to wonder about "what ifs". I still have a job to do.' Naruko thought while shaking her head.

With the Pro-Hero shooting out a stream of ice fire, creating a path of ice while shooting a second stream behind her, propelling her across the ice to go investigate the explosion.

So, what did you think, good. Yep we see here that Naruko is Toya's twin sister and has inherited a very unique Quirk from her parents, being capable of producing light blue flames that are cold rather than hot. With her and Toya both being trained by Endeavor to surpass All Might, only for things to change when they learn Toya doesn't have Endeavor's resistance to scorching temperatures, instead only his mother's resistance to freezing temperatures, leading to him being deemed a failure. While Naruko is still trained with Natsuo and Shoto soon being born, driving Toya further into despair until it reaches the breaking point when he tries to kill Shoto, only for Endeavor to stop him, only for Toya to then attack Naruko leading to a fight between them. With Naruko managing to subdue her brother, only to see the damaged done to him by himself and her, before she tries to help him only for Toya to push her aside, fully severing their bond. Finally we see it's only Naruko remembering that day, with her now being a Pro-Hero herself, along with how Toya "died" (we all know the truth) and their mother's mental breakdown, along with an encounter she had which resulted in her receiving her whisker marks as scars. Before she goes off to investigate after seeing and hearing an explosion. So, review if you liked go away if you didn't.

Storm out