i'm sorry it took a while for me to reply to this. i had to give this one a think! some of these are very random btw. also, this ended up pretty long and clearly having shuake hcs sprinkled in. asasd i hope that’s ok!

AKECHI
- Has a persistent fear of forgetting his mother's face and voice. He never got to save a photo of his mom. He tried to pick up drawing when he was younger just so he could immortalize her and actually has some very amateur charcoal drawings of her he keeps hidden somewhere. Sometime in the future, he commissions Yusuke to paint a portrait of his mom, but–until then–he finds comfort in knowing he's at least sure he takes after his mom. (I also think he fashioned his prince mask after her mother’s insistence on politeness and proper decorum).
- Has done underage drinking because it was an easy way to fit in while attending shido's lavish parties. As a result, he’s built up an amazing alcohol tolerance.
- He and Futaba are half-siblings through Shido.
- Went into liking sweets to add something youthful/relatable to his prince image only to genuinely have a sweet tooth (though he won’t admit it).
- DEFINITELY tried to build up his spice tolerance after the Takoyaki Incident™️. He'd try those super spicy noodles only to last 1-2 spoonfuls and pass the rest to Akiren... Legend has it that, to this day, he's still trying.
- He can’t grow plants because he always overwaters them.
- He’s very, very impatient actually, and he tends to overthink tasks and overload himself with info regarding how to /properly/ do stuff only to get frustrated and say fuck it and do things his own way.
- Being stubborn to the point of being obsessive, he does get good at things he really wants to be good at. That said, he improves in cooking over time. He can’t improvise like Akiren and he finds it hard to cook without instructions, but he grows a list of recipes he’s /studied/ and can make them again and again with terrifying likeness and accuracy.
- Doesn’t believe in astrology but reads newspaper horoscope columns for fun.
- Was part of an archery club (think of Goro wearing traditional archery clothes, holding a bow and arrow with his hair in a ponytail, looking focused under warm sunlight. You get me! And it just makes sense for him!)
- Thought he was aromantic until Akiren. Sometimes he still doubts he might be, but Akiren has a way of making his poor wee heart flutter every time.
- Oh, he's definitely the jealous type. He gets extra possessive about /owning/ things and tends to get petty about it. One day, he gets upset when Akiren suggests he throw out an old sweater Akiren gifted him because it’s already fraying at the edges. He thinks Akiren’s brainless sentimentality might’ve rubbed off on him… and secretly doesn’t mind it cause having things he values feels good actually.
- He doesn't like physical touch. Because of this, he wears gloves as an extra layer of protection.
- BUT after Akiren, he learns that he's actually very touch-starved. The realization dawns on him like a dam bursting. The first time Akiren hugs him outside of emotionally-charged situations, he just /shivers/. He still struggles to initiate physical contact, but he likes it when Akiren shows him physical affection. (You get the gist; Akiren is an exception to a lot of Goro quirks.)
- Despite being touch-starved, he doesn’t like doing public displays of affection. He likes holding Akiren’s hand in public and stealing stealthy kisses in alleyways, but that’s about the extent of what he’s willing to do in public. He does, however, love letting people know Akiren is /his/ in verbal ways, like introducing Akiren as his Boyfriend or inserting obscure information about Akiren that he only knows into conversations just to show off.
- He has a soft spot for Ann and Sumire. They're the first ones he really gets to befriend and hang out with.
- Because Robin Hood is a personification of the strong, dependable, and pure-hearted hero of justice he wanted to become when he was still a kid, I think Goro awakened to him first. Loki came afterwards.
- He felt a genuine sense of accomplishment after he thought he had killed Akiren. But that feeling was quickly subdued and transplanted by anger because how could Akiren let himself be killed?? A worthy rival wouldn't have died THAT easily!. (I firmly believe Goro dropped A LOT OF HINTS ABOUT HIS PLAN TO MURDER AKIREN, even if subconsciously, just so that Akiren could outplay him!!!)
- He never thought he'd live past 20, but after reclaiming control of his life post-Maruki and after countless therapy sessions (which he "aces", by the way -- if that's even a thing), he starts thinking about his future and becomes very determined to outlive Shido and atone for his sins in his own way.
- He would love to learn the saxophone and piano. He has a slightly rough and airy but nonetheless pleasing singing voice.
- His favorite literary genres are: essay collections for non-fiction and mystery and dark academia for fiction.
- He doesn’t have any preferred love language(s) because he gets them all from Akiren. And he gives back equally, though in his own Goro way: showering Akiren with luxurious gifts, always finding ways to spice up their rivalry, making it his lifelong mission to know the intricacies of what happens inside akiren’s head, whispering or shouting his “i love yous” (there’s no in-between), conversely expressing his compliments and other words of affirmation re:Akiren with a clear and confident voice.

AKIREN
- His parents are rich traditionalists and he grew up kind of a sheltered kid. (Listen, ever since I saw that concept art about Akiren's house [some say it's supposed to be Sae's but I like to think of it as Aklren’s childhood home], I couldn't stop thinking about Akiren actually being from a rich family that simultaneously controlled and neglected him.
- He was a pretty active, cheerful, and bold kid. He would also emerge unintentionally as the “leader” figure in his play groups. He only became reserved once he started studying for high school entrance exams and his parents insisted he should act “his age,” which meant studying well, staying in his own lane, and keeping his head bowed down in the presence of authority.
- He was fairly popular at his old school and got into a relationship or two. However, none of them were ever serious; he entered them cause he got confessed to haha.
- He is a master of detachment (but isn't this canon already lmao). He was gunning for a PhD in taking the backseat in life and letting others drive for him. If his life wasn't upended by Shido, he most definitely would've gone down the traditional route: a wife, a kid, a desk job, and a persisting sense of emptiness. That’s no longer the case, but some bad coping habits still stayed (such as shutting down whenever his emotions get too overwhelming).
- He didn't learn cooking because he wanted to but, rather, because he /needed/ to. After seeing that cooking can be a gesture of affection (Thanks, Sojiro!). However, he's learned to appreciate it and has fun learning and cooking his friends' and family's favorite dishes.
- As a neglected child, you can bet that media consumption kept his loneliness at bay. He's watched a ton of movies (and learned a lot of social cues from them from mimicking his favorite protagonists and scenes—he's a theater kid at heart). He has also read a fair number of books even before moving to Yongen-Jaya. His favorite literary genres are personal memoirs and graphic novels.
- His probation diary—though not wordy—still had great prose. I can imagine his writing voice in that diary to be a bit terse, as a result of not wanting to divulge too much in entries others might eventually read, but you can get a glimpse of his thoughtfulness here and there. He definitely had a lot of crossed out lines/paragraphs too.
- He knows how to play the guitar and a bit of piano. He has a rich and deep singing voice with a decent vibrato that would be perfect for opera.
- His awakening wasn't actually /selfless/. I like to think that he saw himself in Ryuji. It was a very similar situation, after all—Ryuji being abused by a power-tripping adult. At that time, Akiren was definitely still seething in anger about his situation. Fighting for Ryuji was also fighting for himself.
- He loves making corny puns and dad jokes but his general humor is morbid. (I think it’s comparable to Daniel Sloss’s humor).
- Because he’s good at reading people, he discovers blackmail material pretty easily. He doesn’t actively build blackmail folders for every person he encounters, but he knows the exact information that would make a person uncomfortable and how to deliver it if he ever needed that advantage. (He never does with friends, but it comes in handy with enemies!)
- His morals aren’t black and white. He’s not against breaking the law if needed (COUGHS murder was an option for him during Kamoshida’s palace, right?).
- He’s very competitive. He likes to think of himself as a good sport, someone who’s genuinely happy for other people who emerge as victors. But, for some reason, he finds himself sulking and sometimes even acting pettily whenever he loses to Goro.
- He has LOW alcohol tolerance. One beer can already makes him a bit tipsy. He’s also a clingy, honest, sappy, giggling-if-not-pouting drunk.
- He’s an adrenaline junkie and genuinely enjoys fighting shadows down in the metaverse.
- He develops a fear of needles and an even deeper mistrust and hatred for police forces after 11/20.
- Has the uncanny talent of being able to fall asleep /anywhere/ or at will (when he’s not feeling anxious about anything, of course).
- Believe it or not, he wasn’t a coffee person before meeting Sojiro and working at Leblanc.
- He’s a hopeless romantic. But contrary to his friend’s expectations, he actually doesn’t like making grand romantic gestures. However, this doesn’t mean his romantic gestures are any less passionate or orchestrated. He just prefers not having a huge audience. He’s a natural at subtler and even seemingly mundane displays of affection like brushing goro’s hand or even stealing a kiss on the cheek when they walk by each other at home, peppering pet names into his responses whenever he can (“yes, dear?” “how was work, darling?”), remembering all the important dates, getting extremely thoughtful gifts, lightening Goro’s workload by offering to do the chores, initiating slow dances in the living room and the kitchen, continuously being enthusiastic about learning Goro’s likes and dislikes, etc. He’d totally wait in the rain and outside Goro’s door with a boombox if he had to, though. And might’ve almost risked arson by lighting up multiple candles for a moody at-home dinner date. Oh, and he definitely discusses marriage with Goro before planning the /surprise/ proposal.
- He undergoes another growth spurt right before college and ends up being half an inch taller than Goro (it irks Goro very much and also makes Goro more susceptible to receiving forehead kisses).