#with enough force and adrenaline you could feasibly stab someone

[uwudonoodle]

Sometimes I sing to myself while putting my hair up in a bun with one of my hair sticks.

(To the tune of Secret Tunnel from Avatar.)

Secret weapon!

In my hair now.

Secret, secret, secret, secret weapon!

[secretanimesideblogidk]

ok so because i am a little bitch who likes their Izuku has a quirk AUs, hypothetical:

technicallyyyyyyy it seems that the vestiges aren’t actually certain that it is specifically the factors of “(one for all) + (inborn quirk)” that equal “burning out the lifeforce of users.” we are of course meant to understand that that is the canon explanation but there’s a little bit of plausible deniability wiggle room and that’s where I live

(also from a purely scientific standpoint “life force” isn’t really... real? like there’s neuroelectricity and ATP molecules both of which are pretty high-energy i guess but anything ‘consuming’ them would basically kill you instantly, not over the course of 20 years. Then there’s telomeres, the shit at the ends of your chromosomes that you lose a tiny bit of every time your cells divide and when you run out of them your cells can’t divide anymore and you die. Something that degrades your telomeres would definitely shorten your lifespan. but “this quirk damages your telomeres” is a little less evocative than “this quirk eats at your life force.” Arguably, either the gene splicing that transmits OFA, or if OFA caused cells to replicate faster (OFA doesn’t seem to have regenerative qualities, but i guess it could be on the upper end of normal) could damage or degrade telomeres, but frankly, lots of things can damage telomeres. this is a tangent.

So a common trope of quirked!Izuku stories where he also gets OFA that OFA enhances his quirk, I think that’s vaguely canon for the vestiges quirks? or at least Banjo mentions black whip being stronger for Izuku, which implies but doesn’t explicitly state, but there’s that wiggle room, the place that I live these days. OFA makes quirks stronger, and as it develops they get even stronger.

Fourth’s (Shinomori, gonna have to get used to having a name for him) quirk is, of course, Danger Sense: a spidey-sense style precognitive.. uh... danger.. sense.... pretty self-explanatory name there. what isn’t self-explanatory is the biological mechanism by which it warns it’s user to incoming danger. Izuku describes it as “feeling like getting stabbed in the head” which, while evocative, does not indicate, say, which portion of the brain lights up when it activates. I’m assuming the quirk signals the parts of the brain responsible for stress-response. It makes sort of logical sense, a “you get a migraine when you’re in danger” quirk is more disabling than anything, but a “survival response gets a head start” quirk would actually help someone survive, say, being hunted by an extremely powerful supervillain.

The quirk is basically your amygdala specifically has the gift of prophesy, so it takes a jackhammer to the hypothalamus and you get your whole hormonal stress response (cortisol, adrenaline, the whole shebang).

So a man with a super-amygdala from 30 seconds in the future walks into a bar gets a super-everything-enhancer that makes him the prime target of the demon lord of the criminal underground. I’m guessing that that “danger sense” quirk got plenty of use. which means that his HPA axis was pretty active too. which means we’re looking at symptoms of chronic stress and making that super chronic stress because the whole thing’s a side effect of the quirk that OFA is enhancing.

Long term effects of long term stress can include fun things like depression, anxiety (which in turn cause more stress), general fatigue, a compromised immune system, heart disease, and wouldn’t you know it, premature aging

(also kind of a side-note bc I haven’t done literally 2% of the relevant research, but “sudden explosive [electrical] activity in a portion of the brain” is kind of in-line with a seizure, and so is the only symptom we were actually given: really bad headache. I genuinely do not know enough about seizures or how to respectfully handle this topic to be all like “this is the epilepsy quirk!” but with this hypothesis of how the quirk works (amygdala Goes Off sometimes), and we have research into what happens physiologically when parts of the brain flip their shit, have a tendency to flip their shit, and repeatedly and uncontrollably flip their shit over the course of a lifetime. idk if it would be rude or even accurate to say this quirk is like epilepsy, but I think it at least has some traits in common, so it seems reasonable to consider health effects of seizures, specifically, what effect frequent, uncontrolled electrical activity in the brain can have on the rest of the body. The essence of sci-fi is taking scientific understanding of the real world and projecting it into fictional situations. Apparently people with epilepsy are more likely to have other chronic conditions like dementia, heart disease, depression, and anxiety. this is a side note because if literally one single person with epilepsy tells me i’m off base here i’m deleting this entire paragraph)

Shinomori says he died of old age at 40, I’ve seen people joke about his quirk being ‘super anxiety’, but legitimately, the combo of “inherently stressful quirk + (extremely stressful lifestyle x frequent use of  inherently stressful quirk) + everything dialed up to an 11 because One For All” is absolutely plenty to shorten someone’s lifespan

TL:DR it’s completely feasible that Shinomori’s quirk, not OFA, is what ended up killing him

(now what this means for Izuku, who now has Shinomori’s quirk, in a world where being born quirkless will not save him from it, is a somewhat sadder thing to contemplate)