Chapter Text
Izuku whimpers, only just holding back tears as he gently prods at the fresh burn on his forearm. The skin is pink and raw, throbbing painfully. He doesn't understand what he's doing wrong. Why won't anyone play with him? Why does nobody like him?
His first day at elementary school and there's already been an incident.
No matter how hard he tries, pleading, reassuring, begging his quirk to settle down, to stop hissing and spitting, he can't stop it from snapping at the other children. A group of kids had ganged up on him, Kacchan taking the lead, as usual. They spent ages just teasing and prodding his sticky red quirk, the other children screaming and giggling every time it reared up in anger and frustration. Izuku had tried his best to ignore them, to pull his quirk back, little fingers threading uselessly through its crimson body. But they'd just kept pushing, until finally one threw a small rock at it.
It snapped.
The rock missed the slime, its dexterous body compressing beneath the throw. But it hit Izuku in the arm, making the little boy flinch and yelp, half in surprise, half in pain. And that was all it took to reveal fangs not yet shown, the creature's hideous gaping mouth stretching wide and large, thin needle like teeth lining a dozen separate rows inside its mouth, like a tunnel of death.
The kids screamed and yelled, calling it a monster, calling him a monster. The next rock thrown was aimed at him on purpose. Izuku just covered his face with his arms and curled into a ball around his hissing angry quirk.
Kacchan bravely approached his curled up form, blasting Izuku away with a few pops of his quirk and consequently claiming the credit for defending the class against his 'villainous quirk'.
It's not fair. He didn't even do anything. His quirk has never hurt anyone! It doesn't even like blood that isn't his.
He sniffles loudly, wishing he could just go home. Crimson red tendrils gingerly trail against his forearms, feeling the heat emanating off his fresh burns, the skin tight and red. Izuku cries a bit as it smears thick transparent slime across his arms, putting the numbing healing substance on the burns that it usually uses when feeding off him. He appreciates the effort, so grateful that he can rely on his quirk to be there for him.
He curls up into a ball, wrapping his arms around his legs and resting his chin on his knees. Little red filaments inspect the rest of his body, searching for any more wounds, they spread out like a web of crimson roots, tapping softly against his skin. He's a bit wet and sticky by the end of it, the crimson slime patching up a few scratches from the rocks, but Izuku doesn't mind. He doesn't think there's anything his quirk could do that would truly make him mad... He'd always forgive it.
"They think you're gross." Izuku mumbles, leaning back against the wall of the elementary school building and holding up the crimson sludge in his lap. It doesn't fit as well in his hands as it did when it was baby new, it's thick viscous body so much larger and heavier now between his fingers.
"I don't care what they think... I love you." Izuku affirms and he finds he means it. Regardless of how creepy or ugly the slimy red blob is, wiry tendrils always reaching, white fangs gleaming and threatening, the surface of its body shiny and wet and occasionally veiny. It pulses in his hold, breathing like a beating heart and Izuku finds himself smiling. He plants a little kiss on the top of it, dark green eyelashes fluttering closed, soft and sweet right on the forehead, just like his mummy does when he has a bad dream. Although, its amorphous shape makes it hard to kiss the top of its head...
How can they not find his quirk as fascinating and cool as he does? Can't they see the potential? His quirk could do so many different things! He's already learned that its spit has healing properties.
His quirk ripples, tentacles curling over his fingers. It... seems to hesitate, like it might be thinking. Izuku tilts his head, watching it convulse and throb, viscous body pulling in tight, tendrils wrapping around one another, bones forming and shifting for the first time ever. He'd theorised it could create bone and musculature, considering it made fangs to feed off him, but to see it grow and shift before his eyes is stunning.
Izuku gasps, holding up his quirk's best attempt at 'cuteness'. It has four legs and a little nubby wagging tail, its jaw opens the wrong way, unnaturally vertical, but that's okay, it's the effort that counts. It also doesn't have ears, just little holes where they could form, eyeless and skinless, its familiar fangs line a horrifying mouth that splits open from snout to chest.
It looks like a small skinned dog, but Izuku loves it more than anything.
"Puppy!!" Izuku squeals, hugging his slippery red quirk as close as he can. Viscous slime sticks to his face in long tacky lines, but Izuku doesn't care. It licks at his face happily, or at least tries to, mimicking the dogs they see at the park or walking along the street. It looks a bit like his neighbour old man Ito's little old dog, but... more wet and squishy. Izuku feels little tendrils reach out and hug him back, his quirk still functions as normal, despite being shaped like a small canine.
"Did you do this just for me?" He asks with wonder in his eyes, his crimson quirk just wagging its new nubby tail and relaxing in his lap.
"I love it!" He squeaks.
"What if... what if I named you Puppy?" Izuku proposes, running his hands down its back as though it were a real dog. His quirk twitches and moves beneath his touch, still wet and slimy, but there's a sturdiness to its form, muscles and bones giving it the capacity for faster, more powerful movement. It can stand beside him now, they can run together and play more games, Izuku’s analytical mind already imagining a thousand scenarios and possibilities.
It seems to like his response, its tentacles picking up his increased heartbeat, observing the way he smiles, the giddiness in his voice. It likes this. Likes being the reason for Izuku’s happiness. It feels good when its host does. Its crimson body ripples in satisfaction, a rough purr emanating from its half formed chest, flesh barely clinging to bone.
Yes. Puppy is a suitable name if only because Izuku chose it.
His quirk slithers closer, tendrils probing at his neck, pushing aside fabric. And Izuku happily tugs his uniform further down, readily providing it full access to his tiny body. The crimson canine splits its face in two, right down the middle, another leach-like mouth emerging from the centre to suction itself to his throat, burrowing into the crook between shoulder and neck. Izuku barely flinches at the pain, well accustomed now to the feeling of fangs sinking into his skin.
He pets it as it drinks, the crimson body anchoring itself further with a few more sturdy grasping tentacles, the tube-like mouth softly convulsing as it gulps down his sweet fresh blood.
The whole process is over in less than a minute, but Izuku finds himself more relaxed and calm, the puncture wounds swiftly sealed with thick tacky slick. Puppy licks at his neck a bit longer, pulling together its 'face' again, and wagging its tail stiffly. It's tongue isn't quite right, more of a wet pink tentacle than a dog's broad flat tongue. It's too long and too coily, but Izuku doesn't mind.
"Who's a good boy?" Izuku smiles, grabbing the crimson canine's face. It pants at him, tentacle tongue hanging out of its sideways mouth, fangs rippling, its eyeless face fleshy and wet.
"You are!" He giggles, happy that Puppy doesn't seem to mind playing the part of a dog for him.
His quirk is so cool!
--
Mummy doesn't like his quirk, at least, that's what Izuku suspects. She is reluctant to touch it and often uncomfortable when it's around. At first, Izuku doesn't really notice all that much, until the day he brings home his slimy red quirk and proudly shows her its brand new 'puppy' form. She flinches away from it, hand held to her mouth, 'that's great, honey'. But it's not. It's not great because mummy doesn't like it, she tells him to put it away, to put 'Puppy' away, once he explains its new name to her.
He's feeling despondent, idly pushing around the food on his plate and begrudgingly taking his collection of hard to swallow pills, only because he knows it will help Puppy grow up big and strong.
He asks Mummy if Daddy is coming back soon from his business trip, but she makes up some excuse about him working extra hard right now. Izuku just wanted to show his father how big his quirk has gotten, show him its cool new doggy form! But that doesn't seem likely to happen anytime soon. He was hoping his mother's reaction would be different than the kids at school, they all screamed and cried, Kacchan calling it an even bigger monster now, although it hadn't really changed much in size, just rearranged some details. If anything it's smaller now, denser, but nobody seemed to care. They all took one look at its strange mouth full of scary sharp teeth and immediately told the teacher on him, claiming he was doing it on purpose to scare them.
Dinner is a quiet affair, Inko spending her time avoiding looking at the crimson tentacles curling across the top of the table, while Izuku tries his best to finish all of his greens.
"Mummy... Do you like my quirk?" He manages to ask, hesitant and fragile. And it takes a moment too long for his mother to respond, Inko pulling on a strained smile as she weakly reassures him.
"At least you have a quirk, Izuku. Things could be much worse." And wow, that came out wrong. She grimaces.
Izuku nods. It could be worse he supposes, although he's not sure how.
Afterwards Inko lets him watch some Mighty Kid cartoons, the All Might themed show is usually his absolute favourite, but today he just feels exhausted. He didn't tell mummy that the other kids were mean to him, she'd only ever agreed with his teachers when they'd said his quirk was scaring everyone who had the misfortune of looking upon it. It seemed pointless to pester her, knowing nothing will change.
He's not really paying attention so he doesn't notice when Inko enters the room, his mother startling at the sight of Puppy latched onto the crook of his neck, crimson tendrils draped possessively over his body.
She screams at the sight of blood, using her telekinesis to throw a nearby book at the pulsing creature feasting upon her precious child. It jolts at the unexpected object hurled at it, hissing and prickling. The hit knocked its fangs from his skin, ripping open the punctures messily. Izuku cries out, confused and afraid and Puppy immediately curls around him defensively, stretching its body as far as it can to protect its host from any more attacks.
Inko puts a hand over her fast beating heart, gradually calming down after the initial panic. She can hear Izuku crying behind the crimson sludge, its rattling hissing teeth bared and threatening towards her. In the dim light of the living room, she can only just make out the blood coating the side of its form, extra wet and slippery where it had been jostled from its secure grip on her child. It had looked terrifying biting her baby, those needle sharp fangs clearly visible as it greedily drank from him.
She slowly approaches, "oh baby are you okay?" Inko asks, but her only response is more weepy crying and 'Puppy' going feral, hissing and snapping and still trying its best to look as big and threatening as possible.
She can't believe that's what it looks like when it feeds... She realises then that she hadn’t actually seen it eat before.
"I'm sorry honey, it just... it just scared me a little, okay?" She gets as close as she dares, Izuku’s quirk manifesting tendrils with sharp spines on the ends that she's never seen before. They're pointed threateningly towards her and she kind of feels like she deserves it, considering that she made her poor baby boy cry.
"Do you want to stay up tonight to keep watching your cartoon?" And while usually Izuku would jump at this opportunity, tonight he just wants to go to his room and sleep, cocooned nice and safe in the lukewarm embrace of his quirk.
"N-no thank you..." Izuku whimpers out, "I'm- I'm gonna go to bed now." He says, scooping up a still hissing Puppy and hurrying to his room. Inko's insides fill with guilt the more she processes what she'd just accidentally done, left standing alone in the living room.
--
Izuku adores his quirk's new form. They can play even more games together now, like tag or hide and seek. The little boy enjoys dragging his oddly shaped quirk to the playground by the park, chasing Puppy across the tanbark and squealing as it follows behind him down the slide. Puppy wags its stubby tail, panting and rippling as Izuku flaps his hands excitedly, pointing in awe at the massive cicada he discovers sitting at the base of a tree.
Inko quietly watches them from a park bench not too far away, ready to leap into action if anything were to go wrong.
"No! Don't eat it!" Izuku cries as Puppy's face splits in half, the crimson creature's horrifying leech-like tongue lingering threateningly over the large bug.
Her baby boy is growing up so fast.
She leans back on the bench, sighing tiredly. It hasn't gotten any easier to deal with Izuku and his quirk. The teachers have phoned her several times complaining that Izuku’s frightening the other kids, that he doesn't pay attention in class and he's antisocial, unwilling to even try and make friends, clearly preferring the company of his icky little quirk. It's harsh, but she can't help but agree with them. Katsuki never comes over anymore, and Izuku doesn't have any other friends to her knowledge. Her poor baby is all alone and there's nothing she can do about it...
Maybe he'll get better with time? She can only hope and fret, and wonder where it all went wrong. How did Izuku even get this quirk, there's nothing like it on her side of the family, and his father's side, well... She assumed they were all fire and heat related, but maybe there's some more strangeness there than Hisashi was willing to admit?
Her pondering is abruptly cut off by the sound of Izuku crying, her son having tripped and fallen while running across the grass. She shoots up to go help him, but the dog shaped sludge is already licking Izuku's scraped knee clean, it's slimy touch calming her son down far faster than Inko ever could.
She deflates a bit, watching her child hug the slimy skinless creature with an adoration she doesn't know how to compete with…