eeee this question is exciting!! UMMM let’s see
firstly, yes, i will undoubtedly write new kinks in the future.
although i’ve looked lists of kinks for inspiration in the past, i’ve never found inspiration that way, i don’t think i’ve ever actually chosen a kink and decided “yes i’ll write this now”. usually i let a concept settle in my thoughts and it’ll pop up when i least expect it, while working on a new fic. (exactly what happened with dean’s thing for spanking in Welcome All Winchesters).
usually, when planning a story, the characters’ kinks and fetishes often just develop as the story develops, until revealing them becomes a natural progression of events. i construct the world around the plot, and the plot around whatever issues the characters need to confront. a kink is usually a way to strengthen the relationship or reveal new secrets, or get a character to open up.
i think i’m up for writing pretty much anything. bloodplay is one my squicks and yet i kind of write it a fluffy way in Manscaping?? i think the only thing i might avoid are hardcore violent things just because i’ve written graphic violence in the past (Angelhawke holy shit, Meg torturing Cas?? definitely sexually charged, and I don’t even think that was properly warned for. i need to re-read the fic and revise the warnings on that thing) and for the last few years i just… haven’t been in the mood for writing violence. i think i wrote all the anger out of me and now i’m just a fluffbunny.
i’ll most likely return comfortably to somnophilia, since i connect that with cas so much, and he’s my favourite to write, on par with dean.
two others that do come to mind: choking/breathplay is one i also didn’t put into WAW despite planning to, but will probably try writing it in the semi-near future. also, if i did mpreg it would probably be in a non-kinky non-sexual way from the perspective of a trans character, so that doesn’t really count.
will almost certainly return to: medical kink (a la Sexier Than Doctor Sexy), animal roleplay/pet play (Dean Winchester the Puppydog), all kinds of variations on the “not gay but you’re weirdly hot”/”oh shit i have a boner for my nonbinary friend”/”no homo but do you wanna make out” tropes (Fight and Fool Around)… which aren’t really a kink but they’re the #1 thing that makes me flustered…. so…… yup.
i’ve written desperation kink/omorashi/not-quite-watersports in Foxfire Blossom (chapters 11, 19 & 23, if you’re curious) and there’s hiiiints of it in Welcome All Winchesters but it’s not written in a sexual way. i was originally planning a short ficlet about it, but it ended up merged with WAW instead - so maybe someday i’ll write another one? not sure. again, it’ll probably be mushed into a long fic, because it’s one of those things where a lot of people will not even want to understand unless they’re invested in the story. it’s always in people’s top 5 squicks, which is less than encouraging if i actually want people to read something with more depth beyond the kink.
things i’ve never been especially interested in include, firstly, a/b/o dynamics (i just don’t get the hype - this despite animal-type mating rituals & dominance being a thing i love dearly (Bad Things With You oh man this one needs some editing)). second: there’ll be hints or themes of bdsm in a few fics but i doubt i’ll ever write a bdsm-centric fic. (thinking about this some more, i might be saying this because i don’t yet have in mind a complete story with developed characters who share this interest, and i have next to zero interest in anything unless i’m invested in the characters. maybe someday i’ll find a place for it.)
tl;dr – yes, i will write nearly anything in the right context. hopefully i’ll be doing what i’m doing now for a long time in the future, and i’ll cover ALL the bases. slowly.
i hope that answers your question?
p.s. i’m more inclined to write a kink if i discover that one or many of my readers are interested in it, because i like to write for A Theoretical Person and if that person is one (or two) random follower(s) who’s into a tickle kink (you know who you are) then it kind of makes me want to write that thing more. *clears throat* Tickle Fight Wasteland *cough cough* (nobody asked for that. i just happened to provide.)
p.p.s. also. slightly off-topic. ages and ages ago i was researching some kink for some reason or another, and came across the term “CBT”. i googled it, got “cognitive behavioural therapy”. and i read that wiki page, and i was like… okay… there’s a kink for therapy… that’s cool. and i thought it was like a mind-control dominance/submission trust-building thing. and a few weeks ago someone on snapchat said they heartily recommended cognitive behavioural therapy to help with depression. and i was like, neat! kinky stuff has practical use in coping with mental health issues!! and literally just now i found a page calling CBT “cock and ball torture”. and now i feel like a fool, but omg i’m laughing BUT ALSO I cANnoT beLieVe– therapy kink. i genuinely thought people got off on talking about their feelings. (uh. that said… it still sounds legit. this is basically all my fics. oh shit it’s me)
