I do be thinking of Hitaka every now and then because it IS one of my dearest OTPs and ngl, your yelling about the bs that was TLJ and TROS (and you are so right and I agree) made me think about it even harder.
Granted, they might as well be an AU of course, but apart from the usual "disregard the canon" energy, this also applies:
My main post-TROS Hitaka shenanigans consist mostly of Hux coming slowly to the realization of being in love with Mitaka, but he has no idea how to conceptualize these feelings because no one ever explained it to him and he didn't used to care either, because he had bigger fish to fry (aka taking over the world galaxy).
Important note is that this is set in an entirely different galaxy because The Finalizer crew (and I guess their loved ones and a bunch of other dedicated Hux stans) deadass said "well, this galaxy is shit anyways, let's go somewhere else" (I have no idea if that's ~possible~ or not, zapping someone with lightning from one's fingertips isn't possible in OUR galaxy, so maybe they just move to a galaxy where "~The Force~" doesn't fucking exist (building on the idea that it (the midichlorians) is actually some sort of malevolent entity that lives off of all these deaths) and so no more space wizardry bullshit (these people are just seriously TIRED))
Anyway, back to Emperor Hux (sorry, I found that title for him hot ever since 2015) being irritable AF because Mitaka is on leave (his family is picking grapes to make wine and of course everyone helps) and at first Hux doesn't even understand WHY he's so irritable and his doctor suggests both taking vacation and also talking to Mitaka because why not just ask him out?
Hux has a hard time because no one taught him how to flirt with/woo someone properly and the entire Mitaka family is just #concerned, but also kinda amused by the situation.
Mitaka is just good-naturedly slightly confused about His Majesty's odd behaviour, but generally takes it all in stride.
Oh Hitaka, my one true loveā¦
No notes, awkward tender everyone-lives post-canon Hitaka is š
If I may blab about my own Hitaka ideas in turn -- I personally love the idea of Hux, slowly through years of acts of devotion and flashes of tenderness, falling for his little Lieutenant [or LIEUTENANT COMMANDER as I stubbornly insist]. And like you said, I'd think Hux really has nooooo idea how to conceptualise, comprehend, or even just sit with these feelings. He doesn't even know where to start, and sometimes that comes out as irritation and pushing Dopheld away, or at best, absolutely fumbling when trying to grapple emotional intimacy. But -- and, I mean, almost any in-depth characterisation of Mitaka is going to be non-canon territory, naturally, but I tend to write him as ridiculously forgiving, patient, and kind when it comes to Hux. He can have his own frustrations of course, loving Hux isn't a walk in the park, but he has a near-unbreakable will to always stand at Hux's side, to show and teach him love, even while Hux at his worst is convinced Dopheld like any sane person will give up on him š„¹
One of my fave post-canon AUs is "Arkanis Exile" where, after Mitaka rescues Hux from the aftermath of TROS, Mitaka and Hux are exiled to the rural outskirts of Arkanis, and Mitaka oh-so-tenderly helps Hux to cope with this new, quiet life of theirs š„¹
And on the opposite sideā¦ is the "The First Order wins" scenario where Hux wipes out Snoke with Starkiller, and give it a few years then he's Supreme Director Hux of the galaxy-spanning Order, with Grand Admiral Mitaka, leader of the Order's Sovereign Fleet, at his side š„¹
And in general my own narrative is that they met all the way back in officer training days, Hux saved Mitaka from Starkiller and Doph sat with Hux as he recovered from TLJ and then rescued him in TROS, and in a life of whirling chaos Mitaka has been the one fixed point of peace and kindness in Hux's life š„¹
