#(but suddenly i wanna know all about exorcist clan marriage legalities!!! are there exorcist prenups??? with clan techniques embedded???)

[defeateddetectives]

*cha cha chas into ur inbox* soooooo what is ur horrible exorcists arranged marriage headcanon AU friend!!! INQUIRING MINDS (ME) WISH TO KNOW!!! :))))

i need to preface this with: i thought about this and thought about this and it is not necessarily a happy story!!!

it would likely be an AU where the sight in the natori clan hadn't completely died out like it had in canon and they were in a much more panicked and precarious state and trying to form a desperate alliance as a last ditch attempt of keeping the name afloat even if only symbolically

shuuichi would be begrudging and prickly about the arrangement the whole time but go along with it to ~save the clan~ in whatever shape or form because he's one of the few stronger ones left with the sight and the de facto heir and ultimately feels responsible

the alliance may have been presented initially as an alternative to total clan subsummation wherein the natori clan gets protection as well but it does...inevitably...lead to...more or less total clan subsummation because who are we kidding??? all parties sort of knew this was gonna happen at the outset anyway what with how the matobas roll. exploiting yet another dying clan? is anyone surprised!!!?

and lbr shuuichi and his clan don't really have a leg to stand on which leads to a whole other brand of angst and interclan drama which also gets mirrored in their relationship for bonus fun anguish points :D

i do think it would be more punchy and impactful if they were a bit younger at the time of this marriage...like 19/20ish? something about them being less polished and savvy and settled into their identities and more easily swayed by the forces around them! seiji is also still the heir rather than clan head at the time!

seiji still held some softness for shuuichi prior to all this and was semi-pining for years but cant really focus on that so much anymore once the arrangement goes ahead and he tries to soften the blow of everything as much as he can (which isn't a lot early on and in his current position)

meanwhile shuuichi may have once had some semblance of softness for seiji mixed with insecurity and a thousand other complicated feelings à la canon but now he's far too busy being outraged and devastated in equal parts to feel anything else. like i said. NOT necessarily a happy story!!!!!!

there's a version where maybe, over time, they could approach some common ground but honestly even if they managed to mutually care for/grow into some semblance of functional partnership and "love" for each other, shuuichi very much would fight the loss of his identity as a natori tooth and nail (and grieve and mourn) and it would definitely colour and periodically sour their entire relationship if not overtly then definitely covertly

and the thing is: if it was anyone else, seiji would be able to nicely compartmentalize and barrel on through but because it's this specific person that he's quietly adored since they were kids, it crushes him as well to see shuuichi so stifled and that fire of his (one of the things that had charmed seiji about him early one!!!) nearly burned out

some time passes and the current matoba head dies and seiji takes the mantle. superficially and politically, they end up presenting a united front and rock the power couple aesthetic for a few years but DEEP DOWN THEY ARE CRUMBLING!!! they go days without speaking to each other behind closed doors unless necessary and it becomes more of a hollow, weary, performance than anything that they get good at doing on autopilot

eventually it comes to a breaking point and, hilariously, maybe the arranged marriage divorce--not a decision made lightly--winds up being the great point of catharsis (and the biggest romantic gesture on seiji's part)--ACTUALLY WAIT I'VE CONNECTED THE DOTS!!! I'VE CONNECTED THEM!!!

THEIR LOVE STORY WOULD IN FACT TAKE-OFF AFTER THEY ENDED THE MARRIAGE AND COULD FINALLY FEEL LIKE THEY WERE ON SOMETHING OF EQUAL FOOTING because that would be so important for shuuichi and also for seiji to let shuuichi have that agency and choose him on his own terms rather than because he was Supposed To

seiji offers shuuichi/the natori clan matoba clan's protection anywayyy because he can (to the matoba elders who aren't about it, he goes: shhh it's alimony!) and yes, i'm probably handwaving exorcist divorce law--which i now want to study for fun--and i know he can't just make these decisions unilaterally but, on a level, this would also be a story about seiji growing into his own power and identity as clan head and getting creative with loopholes that let him meet his own ends

so the end is the beginning is the end and shuuichi does wind up back at square one with a dying clan at the end of the day and hated by his family for being ~selfish and burning that bridge in their eyes

but the two of them also get a proper shot now at Being In Love in some shape or form ON PURPOSE!!!!!

once more with feeling: this is not (necessarily) a happy story!!!!!! not in every way anyway!!!!!!!

bonus epilogue: natori shuuichi shows up at the next matobacorp board meeting with a board seat to his name and half the company shares that he was gifted in the divorce <3 love is real etc etc. [muffled sounds of the succession opening theme playing in the distance] they go on a cute little coffee date after.