[X] Meow? Mrrooow.
Creating functional ears was a challenge, albeit a fun one. You'd had to first grow a reference set on your leg, so you could work out how to scale up to your size, then reshape your skull to accommodate for the new weapons of intimidation; both of which were new procedures for you. While you'd wanted to keep your original ears too for double the hearing power, having double the holes in your skull would just be asking for trouble, even by your standards.
You worked from the inside out, forming the inner middle and inner ear underneath a protective growth of flesh, but left out the Eustachian tube. You didn't know it was called that, but you did know that if it didn't connect to an air supply, the air pressure inside your ear couldn't match the outside, causing the closest thing you'd felt to pain in years: mild discomfort.
Turns out that even if you lacked pain receptors, you were not invincible against distracting stimuli.
Anyway, your new ears were located next to several veins, so you could manually transfer oxygen to the middle ear in place of air when necessary; it would also serve as an alarm clock if something weird happened while you were unconscious or sleeping. Something exclusively relating to rapid shifts in air pressure. It's not paranoia if the maybe existing cultists really might be out to get you..?
In addition to this benefit, your new semicircular canals (which, from what you could tell from the nauseating few seconds between the absorption of your last pair and the new pairs' formation, handled your sense of balance), were much more developed and consequently would help you be less clumsy than normal.
From there it was comparatively simple to finalise the outer ear and various attached muscles. You were glad you'd eaten before, as the cartilage and hair took a lot of energy to relocate and synthesise.
But after all that time and effort, they were complete: a pair of kitty ears were now yours, along with all of the auditory benefits that came with them. Now to become the most intimidating primary school student the world has ever known!
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As you had been banned from the only daycare your father trusted not to let conspiracy theories interfere with your care, you had not spent much time outside your or your relatives' properties, and especially not with other children.
But even if meeting so many new people was a shock, you really should have known better than to introduce yourself by asking if you could eat your classmates.
It was after your parents had drilled it into you that even if it would be interesting to see how other people's quirks worked, and even if the strange, grape-headed boy had said yes, you still couldn't swallow people in public that you were allowed into a different primary school.
Unfortunately, you guessed wrong that the tortoise in the glass tank at the back had been for you. The 'save data' had been worth the terrified screaming of your classmates, though.
Otoronu Primary School was your third attempt. To your parents' relief, you avoided any expulsion worthy behaviour where the teachers could see you, and thoroughly enjoyed your time there. There was so much to learn - although it did eat up the time you were previously free to experiment in.
In your opinion, the best thing about school was most definitely the bathrooms. You didn't need to use them, considering it a waste of recyclable materials, but after meeting its inhabitants, it became your favourite place to frequent between lessons. You had been chasing one of the not-for-eating mice, figuring that seeing as how it had mysteriously escaped confinement, definitely through no fault of your own, that it was fair game. The mouse had been been surprisingly fast, but you managed to corner it in the stall of a disused shower. You grinned with both mouths as it began a futile attempt to fit between the metal bars of the drain, and closed in.
It was just within your reach when your new best friend appeared - a sinuous, red-brown tape, just under the size of your maths ruler, shot out of the drain and wrapped itself around the frantically squeaking mouse. You watched in stunned silence as it latched its head onto the mouse's throat and began to chew.
Mukade, or Red Headed centipedes, are common pests in Japan, and are culturally regarded as a symbol of evil. They like to hide in people's beds, shoes, and clothing. They also tend to climb onto the ceiling, and drop onto unsuspecting victims, because why not. They are terrifying, and the ballsy little demons know it.
You named him Omu.
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After that, you made a point to visit Omu every school day, the centipede always happy to give your fingers a hug whenever you pulled off the drain to pick him up. The venom he injected into your bloodstream every time was stored where one of your redundant kidneys was previously located. You could have created a gland to create it for you from Omu's save data, or even synthesise it manually, provided you ate the right materials, but the little mukade was always so enthusiastic to gift you with some… You had no idea what you were storing it for, but maybe you could incorporate it into the next addition to your physiology.
Your dad was away again on a 'business trip' in (he actually just wanted to visit his parents without upsetting your mom, so that was the official excuse - she did not get along with them for some reason), and would be returning the night before his birthday.
You had decided that you wanted to surprise him by growing a tail, in order to look more like him. Your mom had initially protested, but, after realising the futility of attempting to dissuade you, agreed that your dad would appreciate the gesture.
You repeated the same basic method you'd used for your ears, creating a reference from the cat's data, then scaling up. The finished tail couldn't be too long, only about three feet or your current heart started to tear itself from exertion, and required the depletion of an entire freezer's worth of meat to create the required muscle mass, but it was so worth it. Until you fell over backward and crushed the majority of the bones inside it. You'd had to skimp on the density to make it light enough to lift, which was fine when the tail was suspended, but too much uneven pressure and you had to waste time [focusing] to repair the damage.
Maybe this was why reptiles had scales? You examined the sole piece of Nidhogg's 'data' and there was no way you were going to waste so much time repairing each individual part! Something like Omu's armor would be more efficient, as it wouldn't spread your concentration too thinly when [focusing]; you combined the material of your bitey friend's carapace with the structure of a tortoise's, in order to account for the size increase, to create some thin dermal plating along the thicker sections of your tail, using up several bags of sugar in the process.
You tested this improvement immediately by accidentally falling over again, and while the bones didn't break to the same extent as the previous time… well, you were glad you couldn't feel pain. Although the damage could be fixed in a fraction of the previous time, you really needed to fix that balance problem; the root lay in your legs, which were unsurprisingly not suited to compensating for the additional weight of an armoured tail.
You checked the clock, one in the morning, plenty of time to have some fun - this time, you took a different option with your legs. They were relatively simple to edit: slowly transfer the preexisting materials around to the different sections of your leg, test, heal, repeat.
Adding joints was pointless; digitigrade was definitely the best way to go.
Test, heal, repeat, change, test, heal, repeat, change, test.
Got it.
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After returning from winter break one year, you discovered that you may have made a mistake in assuming that Omu was male. You'd reached down the drain as usual, intending on saying hi and making sure that was getting enough food, and pulled out an angry ball. An angry ball of cuteness that was curled around a clutch of eggs.
After squealing excitedly for a minute, they were all placed inside your mouth - gently, so as not to damage any, and you made another discovery.
'Save data' usually contained plans for a few parts of the whole organism; it was why you couldn't make a full replica of Nidhogg for whatever reason you'd want a dead snake. But this stuff… It had everything.
While there was no difference besides quantity between the [potential] in the eggs' data and that of Omu's, you felt that this would be an important clue in identifying what exactly 'save data' was...
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As all your friends lived inside you, there was no need to be upset about your graduation into junior high. And anyway, there were so many new things to learn! So many new people to accidentally scar for life!
However, there was one thing that you simply could not tolerate about junior high school, and that was the uniform: trousers simply did not accommodate for your tail or your legs, so you couldn't walk in them without tearing. A skirt worked in theory, but your tail was attached through a bulky section of muscle trailing up your back, not magic, so skirts just rode up to somewhere around your ribs. Blazers and ties were pointlessly restricting accessories, so you refused to wear them on principle. Shirts were your worst enemy, concealing your secondary mouth in a futile attempt to bring your cuteness down to the level of a mere mortal. Plus, the buttons kept getting stuck between your teeth.
What was even the point? You lacked any of the useless parts that others had to cover up, being the owner of a vastly less wasteful digestive system that could even break down metal if given enough time and acid. That had been awkward to explain to the doctors. Hell, if they wanted to colour coordinate, you could just dye your skin black and white by changing the levels of melanin - if you added a few flaps of skin around your wrists and ankles, nobody would be able to tell the difference!
Due to your obstinacy, the only local option available to you was Orudera Junior High, a school so desperate to for a graduate to go into the acclaimed 'hero academy', UA, that they would overlook pretty much any inappropriate quirk usage. It had not occurred to the faculty that it was possibly their graduates' resulting lack of discipline regarding their quirks that cost them their entrance exams.
Yes, please continue using your potentially lethal quirks with little to no regard to civilian casualties - it's precisely what we look for in a hero.
You didn't complain; they let you walk around effectively naked.
Junior high was a lot more intense than primary school, not just because of the increased workload. You were infinitely grateful that you'd followed your mother's advice on underselling your quirk, because to many of the students, the UA entrance exams were the final round of a year gauntlet of grade sabotage and physical violence. While it was only the most competitive of students who instigated it, targeting anyone with a quirk they believed could pose a threat to their chances of getting in, the apathy of the faculty left victims with a choice between retaliation and giving up on their dreams. You mostly avoided the conflict, as popular belief was that your quirk let you eat animals and add the best parts to yourself, a 'relatively useless power' for combating villains. They were thirteen year olds, not zoologists.
Very rude thirteen year olds.
For that reason, you avoided socialising almost entirely until the day you decided to follow the blond from your physics class during break. While you refused to even think of attempting to copy quirks, because you were going to be a hero through your own power not someone else's damn it, you would allow research into their required physical changes in order to improve your own body - such as how Explody McAngermanagementissues's hands didn't break or burn from the use of his quirk. You needed the former so that your legs would stop breaking so often, and the latter because branching into explosives sounded like a Really Good Idea that would definitely not end badly for you. Or your health insurance provider.
You'd successfully tailed him and the rest of his friends (?) to an empty classroom, when upon following them inside, you spotted Bakusomething verbally abusing what appeared to be a sentient shrub in a uniform. You couldn't see the victim's face, as they had their back to you, but what you could see resembled a small bush, at least.
Oh dear. Blondie was raising his voice. This could easily develop into a fight. Wait - grass types are weak against fire!
You have to do something to interrupt them...
Main Action:
[ ] Screw Bakuxxx and his harem (?), heroes don't stand by and watch! It is time to unleash your lizard heritage.
[ ] Break the ice by introducing them to your friends.
[ ] Break the ice by nomming the blond one.
Additional actions: Write-in
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AN: And so the canon derailment begins. I can almost hear the screams from here.
The following parts definitely won't be as long as this, sorry. I just wanted to write both options. Plus, I greatly underestimated how long Japanese primary school lasts when planning this, and only one major upgrade in years is a bit… Oh well… it's only really a basic aspect of one area of your quirk. Once the prologue's over, improvements are only coming from additional actions. As in, do X and try to Y. Unless I get bored and give you another free basic aspect. I reserve my right to be indecisive.
Giant centipedes will eat anything they're large enough to. If I don't post ever again, it's because I've been arrested for all the weird shit in my browsing history from researching this part.
Unrelated, but I once saw a group of thirteen year olds call a tapir a baby elephant. And not as a joke.