[X] What a delicious looking snake
A shrill squawk caught your attention - one of the other children had just spotted the cutest little snake by his foot and you love reptiles and you - oh. You just ate it. The other child screamed even louder.
It flailed all the way down, until it reached your stomach and became you-but-not. Your eyes lit up; this was so much more interesting than the wasp - so many different parts that you didn't even know where to begin! Wait, now you did.
Unlike the mostly harmless grass snakes of other countries, Japanese grass snakes, locally known as yamakagashi, are not only venomous, but poisonous to boot. You would later reflect on this fact with the conviction that whoever named for them must have had a sick sense of humour, but you were currently preoccupied by the fact that the adorable widdle snakey had just caused internal bleeding. You frowned, attempting to disconnect the stretchy bits that made it move, and failing, which was strange, as you had thought that you could do that. You tried it with your left arm, and succeeded. Oh, it was probably because the snake parts felt different: the snake wasn't really you, so you couldn't change it as much. You were great at this deduction stuff!
As much as you wanted to play with the snake, now dubbed Nidhogg, you had to deal with the bleeding first. However, you were not one to let a little pesky haemorrhaging stop you - calling on the skills earned through the countless hours of gameplay sacrificed to the merciless gods of Low Battery, you scrambled for a way to save your data.
Tuning out the panicked daycare minder, you pored through the snake's coding, until you discovered, nestled inside its spinal cord, tiny pieces practically singing with [potential]. Spurred on by the concerning movements the choking snake was making, you [pulled] one of the fragments into yourself, and set about letting poor Nidhogg out.
---
By that point the daycare minder was crying; he was a good person, right? What had he done to deserve this? But now that weird little kid was going to die and the ambulance wouldn't get here on time and they were so going to get sued for this. At least they had managed to get the rest of the children to come inside, although they, like himself, were viewing the scene with mixed levels of dread and anticipation from the other side of the sliding glass doors. This was a choice they would regret. Particularly around the point when the now shirtless child put their right arm through the side of their own chest.
---
Once you got the hang of it, moving your organs around was easy: just keep your hand away from the arteries, blocking off smaller blood vessels and repairing tissue damage as you go. The secret is to lie down so that nonessential processes can be temporarily shut down in order to focus on more pressing matters, such as the hand in your chest cavity.
Fixing the damage to your stomach hadn't been too difficult, even with the snake venom complicating things, as you had previously closed off circulation around the bite area once you realised what had happened. Then it was simply a matter of [moving] the weird bad stuff the snake put in you and the lumpy blood from around where it touched out of the area, spitting it out, and [focusing] on the damaged area to accelerate the healing process.
Saying goodbye to Nidhogg had been difficult, but it was for the best; as you watched his bloodied form slither off into the undergrowth, you consoled yourself with the knowledge that he would find someone better than you, who would give him more from a relationship than you ever could.
But when it came to getting dried blood out of bedsheets?
You gave up, flopping back down onto the soaked hospital bed. It had seemed like a logical decision at the time; the doctor wouldn't let you leave without a parent because of some stupid reasons like "you've lost a lot of blood" and "you don't even know your own address" - you're nearly four-and-three-quarters, you don't need her opinion! Anyway, you'd had nothing to do after she took the potted plant you kept attempting to force down your throat, and so had come up with the bright idea of adding a second mouth, to avoid getting caught again.
One thing led to another, and you were soon in the process of deciding which organs you could merge into a larger stomach.
'What is that? It doesn't even do anything!? Don't need it. Those don't do anything yet, but I'm completely fine, so it's probably not important. What do those blobby tubes do?
Eventually, you were the proud owner of a greatly expanded stomach, as well as the proud recycler of your appendix, intestines (which turned out to be redundant, due to the fact that after a little practice using the snacks the doctor left you, you found that could do everything they were supposed to manually anyway), and undeveloped reproductive organs. There had been a bit of a problem when part of it had started dying for no apparent reason, but it worked fine after you had the idea of attaching more of the bleedy strings to it. Thankfully, the doctor had set up a blood transfusion before she left, inadvertently saving your life, not that you were aware of it.
Your secondary mouth connected directly to this, and took the form of a highly visible, vertical slit running from just beneath your ribcage to your pelvis. It had no complex mechanism behind it, no purpose to it being visible other than aesthetics; you would simply split the skin along the indent and shove your victim in by hand.
You'd wanted to add teeth, but you didn't have enough of whatever your teeth were made of to do it.
Unfortunately, you were now lying in a pool of your own blood from where your concentration had slipped earlier, causing one of the big bleedy strings to realise that it wasn't currently attached to anything for a second. This irritated you greatly, as you had been planning on not getting caught. The fact that the doctor would definitely notice your new mouth regardless of mess eluded you.
Oh well, at least you killed a few hours.
"Thank you for signing, your child is right through here"
"Hi, mom!"
You learned a lot of new swear words that day.
---
After the initial shock, your family were ecstatic that their little Kaede's quirk had finally manifested, disregarding how unusual it was that it didn't follow any of the established patterns that quirks did. This was mainly because you, being far from eloquent, lacked the vocabulary to properly communicate what you knew of it, and as a result, they were under the impression that your quirk was centred around eating potted plants while being unintentionally terrifying. Your grandfather was pleased. He'd bet some money on the quirk being related to the latter aspect.
Eating a plant was actually an incredibly disappointing experience. You'd assumed that you'd get to sense many more interesting parts from something so different to another animal, but all your preparation was for nought. No matter how many plants you tried, they all felt more like regular food than the snake or wasp: just a vague awareness of what it was made of. With fresh plants, there was a slight stronger sense of 'like you', but it was like the difference between trying to swim in a hurricane and trying to swim in a hurricane with a headache.
Your quirk was picky that way. What makes something 'like-you', anyway? You didn't know how to test it, and had no idea how to go about asking someone for help.
When the initial excitement of discovering your quirk began to fade, a whole week later, you realised that you had no idea what you wanted to do with it. On the same level that other children knew how far their joints could bend, you understood that you could change yourself in far more ways than you already had.
And you still had Nidhogg's 'save data' lying around...
You felt a little disappointed at your lack of creativity; you couldn't become a hero with just the ability to eat people, after all. What to do, though? You decided to look for inspiration.
Main action:
[ ] You watch [blue documentary], and thought about how you could replicate what you saw...
[ ] You read the start of [book about a different world of superhumans that is definitely not intended for your age range], and thought about how you could replicate what you read...
[ ] You watched [drilling oriented anime], and thought about how you could replicate what you saw…
Additional action(s):
[ ] Write-in
---
AN: Well, that escalated far quicker than I intended. Hospitals in that universe probably have to deal with a lot of weird shit, seeing as it's canon that small children are generally left to learn how to use their potentially dangerous abilities by themselves with little to no professional oversight.
To reiterate what you know of your quirk: you can 'change' yourself using a surgeon's tools, things like wasps and snakes with a hammer, and plants and food using only threatening glares. You can't switch tools.
Don't get used to getting automatic upgrades like this, though. Or such little input in what happens, it's just for the first few parts. That would just be boring.