I got bit with the bug for this ship a couple weeks ago, and while I'm writing a little fic for them, you guys can have these headcanons
Lucifer and Vox are romantically and sexually involved while Alastor is their queerplatonic partner
Lucifer and Alastor were actually the first to become involved with each other, then (somehow) Alastor and Vox worked through their differences and became qpps as well
Lucifer DID NOT like Vox at first - he'd heard what happened between him and Alastor and was sure he was trying to hurt Alastor again. It wasn't until Alastor got sick of the protectiveness and forced them to hang out that the pair actually realized their chemistry
Lucifer and Vox are both rich and treat customer service employees like shit
Alastor - who grew up poor and is still not exactly strapped for cash (I'm a broke Alastor truther, sue me) hates this. Both he and his mother worked in customer service when money was tight while he was alive, so he always tries to treat them with respect. He'll take money from whoever was the biggest asshole on their nights out and use it to give the waitstaff large tips. Nights out almost always end in the silent treatment, but our boys are dumb so they don't know what they did wrong or understand why it was wrong when Alastor tells them
Don't worry, they get it eventually and start working on themselves
Vox and Alastor both prefer coffee while Lucifer likes tea more
Vox has the best sleep schedule, Lucifer alternates between not sleeping at all and sleeping for 19 hours, and Alastor sleeps at most 3 hours per night due to crippling insomnia - though he like to tell everyone that not sleeping is a choice in order to seem more mysterious and intimidating
Vox and Lucifer had a field day when they found out Alastor was ticklish. Alastor pretends to be annoyed every time they gang up on him, but it actually reminds him of the rare happy memories of his childhood, so he lets them keep doing it
Vox and Lucifer will binge their favorite shows together and come up with the wildest conspiracies about them
When they sleep in the same bed, Alastor and Lucifer use Vox as a makeshift heater
Alastor is fine with being kissed - making out is a definite no - but he doesn't kiss. He bites with affection. He never draws blood when he's being affectionate, but he's not always gentle either. It isn't uncommon for the trio to be laying in bed and Alastor just starts biting whoever is closest
For someone who is supposedly with the times, Alastor and Lucifer had to explain asexuality an ungodly number of times for Vox to finally understand it - a byproduct of being with Valentino for so long
Alastor still refuses to allow cameras to see him clearly, just to tease Vox when they aren't around each other
Despite his claims, there is actually a wide array of modern music that Alastor enjoys, but despite his southern roots, Vox found out the hard way that Alastor will throw hands if you play country around him
Alastor and Vox love making fun of Lucifer for his height - until he shifted into a form that was a good 5 inches taller than both of them just to shut them up. Lucifer wishes he'd had a camera because he'd never seen them both so flustered at the same time
They have competitions about who can come up with the best dad joke/corny pickup line, and they usually end up laughing so hard they can't breathe by the end of it
They also love trying to make each other blush. Lucifer turns bright gold when he receives genuine affection. Vox overheats when either Alastor genuinely laughs, or Lucifer turns on the charm. Alastor hates that he turns bright red with either genuine praise or when his partners surprise him with something he enjoys (knowledge of jazz/radio, cooking authentic Creole meals for him, expressing real interest when he actually gets invested in something, etc.)
All three of them have weird little hyperfixations - Lucifer with his ducks, Alastor and furbys, and Vox is absolutely fascinated by the existance of Pastafarianism (the worship of the Giant Flying Spaghetti Monster). They all tease each other over their hyperfixations but will listen with the same fond looks when one of them starts rambling about it
Speaking of furbies, when Alastor unleashed the fabled Furby Organ, he played "Symphony No. 5" on it perfectly, and Lucifer and Vox were both awed and horrified
Lucifer always worries they will leave him just like Lilith did, and they both do their best to comfort and assure him otherwise
Vox is afraid that Alastor and Lucifer secretly think he barged in on their relationship, and they will playfully talk shit about each other until Vox is convinced he's both wanted and plays a vital part of their relationship
Alastor fears that they'll either decide he's not good enough because he doesn't like sex, or they'll find out he doesn't own his soul and cast him aside. They don't do anything about this because Alastor never tells them about his fears, instead letting them fester until they manifest as constant nightmares that he also doesn't tell them about
They have each others favorite food and drinks memorized down to the seasoning and temperature
Vox's love language is gift giving, Lucifer's is quality time, and Alastor's is - ironically enough - physical contact. Of course, this makes his touch aversion even more difficult to navigate
All three of them are incredibly touch-starved
Alastor learned how to rewire and fix televisions purely for Vox's benefit - he read three different owner's manuals and practiced on the tv in the lobby in secret
On Lucifer's bad days, Alastor and Vox will regularly check on him and slowly coax him out of bed
Vox is prone to viruses despite his firewalls, and Alastor and Lucifer take turns playing nursemaid when they get bad
When they learned Alastor suffered from panic attacks, Lucifer and Vox spent hours researching ways to help during, before, and after an attack, and learned the signs Alastor had that he was becoming distressed so they could make them less frequent
On that note, when they discovered that he had trichotillomania (hair pulling disorder), they got him different fidget/picking toys to negate the urge to pull his hair
That's all I have for now, feel free to add onto this if you want, I'd love to hear your opinions
I'm back on my bullshit, so buckle up buckaroos, it's gonna be a bumpy ride
ALSO, before I forget, I received an anon ask about if it was okay to write about my headcanons and such, and that is absolutely 100% okay!! I would love to see other people's interpretations of my thoughts, that's why I put them out there, so please feel free to interpret them as write about them, just give me credit, and let me know so I can see it!
Halt snorts when he laughs, but only if you really get him going. When he does, he'll turn bright red and try to cover his face, which works all well and good if the reason he's laughing so hard is because someone caught him super off-guard with a joke. However, nine times out of ten, he's only laughing that hard because someone decided to test his ticklishness (usually Crowley, but the others do it too once they find out), which means he can't cover his face without almost immediately moving his hands to grab the wrists of whoever's attacking him out of reflex
Speaking of Halt being ticklish, he would never admit it even under threat of death, but he actually doesn't mind being tickled. It shows him that people care enough about him to get close and try to make him laugh. He also finds it kind of nice to just be able to let loose and laugh when he usually can't out of fear of either vulnerability or tarnishing his reputation. Needless to say, if he lets you get away with tickling him, it's the ultimate sign of trust (kind of like a cat laying so its stomach is exposed and trusting you not to attack it)
When Halt is focusing on something, he has a habit of sticking his tongue out of the corner of his mouth (which I believe is something Horace actually noticed in KoC)
Halt has a bad habit of biting the sides of his fingers when he's nervous. If Pauline or Crowley happen to notice, they'll gently bat Halt's hands away from his mouth
If there is ever a mission that requires disguised infiltration in a high-class setting, Pauline and Crowley will almost always be the ones to handle it - and not just because of how well they coordinate off each other and work together. The main reason is because they both noticed how tense and jumpy being in that sort of environment made Halt after their first such mission. He never brought it up to them, and until KoC, they didn't understand the reason why (though they both had their theories)
Due to his royal upbringing, Halt is actually a very good singer and can play the piano as well (I don't know if the piano existed at this point in time. It's fiction. leT ME HAVE THIS)
Halt said that he can't face a plate of shellfish without throwing up, but he was underselling just how much even seeing a serving of shellfish deeply disturbs him. He'll usually start having a panic attack within the first few minutes, his mind telling him that the food is laced in poison, and that he is 16 years old and back in Clonmel.
Halt and Will both have severe PTSD, but only Halt is ashamed by it. At first, Will was ashamed of the way he was affected by his trauma, but Halt and his other friends shut that down really quick. Halt however, never had anyone who knew about what he went through, so he never had anyone to tell him that his struggling was okay. He was afraid that Will would end up the same way as he did, which is why he fought so vehemently against Will thinking he was doing a "bad job" of handling his trauma
Halt is very much a "do as I say, not as I do" kind of teacher. I mean look at him. This man's never even heard of self-preservation, but god forbid anyone he cares about pulls some self-sacrificing bullshit (that he pulls maybe 30 seconds later)