family
vincent, lola and agnes were inseparable as classmates before each one of them followed their respective carreer paths. they reunited years later and didn't stop working together since. alioth was raised by the three of them, further reinforcing the relationship of work colleagues/life partners that they had going on. grace was born around the same time as agatha, vincent's sister, had her son dennis. agatha and his brother vincent got along well enough to leave dennis playing in vincent's mansion almost every week, so grace and dennis developed a sibling-like relationship between them and alioth, who enjoyed a little too much having the role of an older brother.
love
moon and alioth don't actually live together, but he spends so much time at her place that you could say they technically do. alioth hates the atmosphere in vincent's mansion, given his father's reputation in both the scientific community and the citizens in general. he's far too excentric and self-centered. he rather finds comfort in moon's house with her messy kitchen full of half eaten jars of jam and her walls crowded with paintings waiting to be finished and her 10 different hair scrunchies thrown around everywhere.
pets
dennis is really bad at interacting with people. like, really bad. he's tried talking to some classmates before, but his weird manners around others are almost always misinterpreted as being mean or uninterested. he tries a lot though, as he only feels comfortable around his family (and hibiki, after meeting her) and wishes he could have more friends to have interesting conversations with, since he finds himself a very uninteresting person. animals don't make him feel as intimidated though, and they even get close to him at random places. and even though dennis chooses to don't have any pets, he always welcomes with a smile when birds or stray dogs come to greet him.
fear
there's a weird mix of reasons why hibiki is doing magical girl stuff right now, but the most important ones are that she was tired of her own reality, moon couldn't transform into her magical form anymore and the adults needed any person to replace her as quickly as possible. she's now working on her own feelings about this whole situation while helping out the adults and trying to understand moon's past and how it relates to the rest of the cast.
sadness
dennis' relationship with his memories of agatha are complicated because he is aware that she abandoned him, but also he remembers all the times she cried to fall asleep and wouldn't get out of bed for the whole weekend. he never asked when her mother left him in vincent's mansion and never came back, he was far too scared to hear the answer. sometimes he wishes he had asked when he was younger, it seems too late now to be asking stuff. how would agnes, the woman who raised him, react if he asked about agatha? dennis knows it doesn't make much sense but still isn't brave enough to ask about her. so now he lives just with the memories of them together.
joy
the three of them don't have much in common besides their weird and hurtful relationship with childhood memories, but that's enough for hibiki, grace and dennis to completely understand each other and become inseparable after getting to know each other.
past
hibiki was always considered a problematic child, both at school and home. her parents clearly didn't know what to do with her and because of this she lived with various relatives in her early childhood, never having a parental figure to trust and search comfort on. it was always her classmates at school the ones who gave her support and attention, even though she was constantly in trouble for talking too much and being an irresponsible student in general.
future
grace always knew that her mother wasn't really good at this mother-ing thing, but she admired her so much that she forgave her for her whole childhood. even when lola didn't notice her absence when she slept at her classmates' place for a week, even when lola didn't have a hint on what subjects she was studying at school, even when lola let her move out and have her own apartment at the age of 14. well, she did want all these things and that's why she did them in the first place, but she would've liked a bit of concern from her mother after all. but lola is still the person grace looks up to the most, and that's why her biggest goal in life is to be as great or even greater than her.
alternate universe
i have an AU in mind where they are classmates in a normal school in the normal world and have normal lives. they deserve it. also grace is a magical girl here just because she's pink. no other reason. also moon and alioth are magical mascots (not pictured here).
hobby
moon has always been a creative person, and that's the part of herself she's most proud of. she loves making things by her own, these being paintings and drawings, fixing clothes, cooking, and playing instruments sometimes. for these kind of things is that she feels most comfortable around old people and visits regularly her old neighbours just to drink tea with them and talk about various things.
talent
alioth being the oldest child in vincent's family, he's been exposed to the academic enviroment since he remembers. he has an amazing facility to understand new concepts and that's why he wants to work in science related stuff just like his parents. it's kinda boring though, once he notices most (if not all) of his life is basically surrounded by old people with great egos just because they're smart.
power
when lola asteria published arguably the most important research about demons in the past decades, vincent leon was immediately interested in working together to test the new knowledge that humanity now had about these mysteryous beings. he doesn't feel threatened by demons and never has been, but the infinite curiosity and the selfish goal of his name being recognized as someone who made history made him take decisions that changed the lives of all the people close to him.
good / evil
demons have extremely fragile bodies and have to constantly seek for food to continue living. they also don't show themselves to humans unless it's necessary for their survival and only get to work at night, this is the reason why people know so little about them though their existence has shaped for centuries the way people live and relate to each other.
young / old
moon ran away from home at a really young age and ended up being adopted by angelique, an old lady who owns a store where she sells herbs and plants and flowers, and has a lot of interesting stories that really resonate with moon and what she's going through right now. angelique is easily the most interesting person that moon has known in her whole life, and she alone makes it worth all the difficulties moon had to go through when she decided to leave her parents' house.
opposites
it doesn't take long for grace to notice that hibiki's ideals and goals aren't really what she considers correct. this and some hidden feelings on jealousy towards her, makes grace make decisions that she never knew she would be considering. she'll do anything to defend what she thinks is right, even if this means playing as the antagonist for her best friend. she would really like for things to be less complicated than this, though.
sci-fi
this world has well developed technology, and it plays a big role in the lives of some people like alioth and dennis who, because their parents, are constantly in contact with the city defense mechanism for demons and also the magical girls who are using the same power that the demons have, but was modified by the adults to be used at their advantage.
fantasy
this drawing isn't canon because moon and hibiki aren't magical girls at the same time, but i still think it would be nice to see them fight demons together... idk what to say besides that i love them very much.