I'll ask Horobi though I'm sure somebody else already has, but I'll throw in Miki too for fun ^^
No one has, actually. ^^; I don't have many friends. I'll do both.
Favourite thing about them : Uhhh… Everything?? He's amazing, he's such an interesting, complex, powerful character, even when the writing is fighting him tooth and nail.
Least favourite thing about them : The way he was treated, both by the writing and by the audience. I need to know what absolute insanity was going through Takahashi's mind.
Favourite line : Oh, gods, so many, for so many different reasons. Top are probably his last words to Baby Jin, his 'we are not slaves to humanity' lines, and when he finally said Fuwa's name in the VCinext, however painful the rest of it was.
BrOTP : Uhhh… Jin's his son, well Baby Jin was his son, Neo Jin is like… His son's imperfect clone? Probably Ikazuchi and Naki, in a way, although I am fond of at least him and Ikazuchi being romantically involved in the past, pre-Ark, but by the present Horobi is a different person bc of everything he's been through and it wouldn't work out. It's not perfect bc they both turned on him for having trauma, but he has a better relationship w/ them than any other character besides…
OTP: FUWA. I realised pretty fast the were my faves and so wanted them to interact, and then I started au shipping them, and then they got a rivalry and by that point I was getting parallel/not so different 'being manipulated/used/controlled' vibes from them and then the show started following through and I was just gone. And then the show fucked me over and was like 'lol that all never happened,' but they cannot undo what they have done. Horobi and Fuwa invented enemies to lovers and I will die on this hill.
NOTP: Several, for different reasons? For ex him and Gai and him and the Ark are things I don't actually see as healthy or want to see in canon, but like exploring bc they are messed up and twisted and I like tormenting my favourite characters. Like 'my canon' features both depicted as abusive and being part of why Horobi's so messed up.
Meanwhile, Yua and Aruto bc they treat him terribly and do not care about his well being at all, and then Jin and Izu bc the former is/was his son, the latter is a) absolutely not capable of consenting to any kind of romantic relationship, b) is too young for him, and c) also doesn't care about his actual wellbeing. (same could be said for Neo Jin, honestly)
Random headcanon: Horobi likes watching Fuwa make faces. He is content to watch Fuwa's expressions for hours.
unpopular opinion: Horobi was one of the two least at fault for what happened in that warehouse. The other was Izu. Everyone else had a large hand in enabling/provoking/allowing that situation.
favourite picture of them: Uh, anytime he's onscreen??? Okay, fine, I’ll use this one.
Favourite thing about them : So, so much. I may have only met him bc of Sunagawa, but I am absolutely attached to him. I haven’t mentioned him recently and I feet bad about that, I’ve been going through some stuff, but I still love him. I guess you could say just how… Realistic he is? Like he’s very realistic for a young, rather troubled man thrown into a situation that’s just way over his head and way more complicated than he’s equipped to deal w/ and eventually breaks him down, which… I just feel all the time.
Least favourite thing about them : How little he shows up! :( On the one hand, like I understand he’s not the main focus, and as far as parts in the greater plot go, I don’t feel like he necessarily needed anything else. It’s not like Zero-One where Horobi’s lack of a past left a massive hole in the narrative, the story as a whole doesn’t need Miki to have more focus, I just would like to see it.
Favourite line : Oh… Oh, goodness. You’re um. You’re putting me on the the stop. But I’m gonna stretch this a bit and just say, from the musical, his part of the song w/ Mister Wonderful Baritone and Cartwheels With Guns (what are their names again???), like after he’s revealed to be a Fury for the first time. If anyone knows what I’m talking about. I can hum the start of it.
BrOTP : … Hmmmmm… I guess I could say Souma for this? Or maybe Chizuru? I guess Itoh could count although I see them as a little complicated. The thing is my knowledge of actual Hakuouki is very limited bc I only became involved bc Sunagwa (which I’m okay w/), so I’m not so familiar w/ the other characters. Although the musical convinced me that he, Souma, Chizuru, and Nomura could have been Squad Goals™ had things been different.
OTP: Souma, coincidentally. I don’t need them to be romantic, but they are so similar and so balanced and the parasols… Ahhhh. I’m so in love w/ their duet during the final duel and I just. I’m love them. Angry gruff guy and super anxious polite guy, but they both have other layers like Miki is actually quite anxious and unsure of himself and Souma is capable of great badassery when called upon.
NOTP: Uhhh… Not really? I guess the typical ‘don’t ship them w/ family’ kinda thing.
Random headcanon: Gotta filch this from you actually, but the idea that he’s some sort of more advanced kind of Fury, maybe bc he’s just taken to it so well, or Koudou was using him for further experiments… But him finding out that things that usually kill regular Furies don’t work on him, and the poetic tragedy of him being driven to the point of wanting to die but never being able to.
unpopular opinion: Uhhh… I don’t interact much w/ the wider Hakuouki circles, so I have no clue. I don’t think my sorta shipping him w/ Souma is exactly unpopular so much as it is not something most people pay attention to.
favourite picture of them: ANY. AGAIN. But to keep in the vein of emotional moments/meaningful expressions and movements/Sunagawa being good at acting…