Areum Roseroad's a middle child, between older brother Daris and younger sister Senna. he becomes the patriarch of the house when their father grows too senile. Daris is the lead engineer/architect of the family business, Senna married a man in their ancestors' homeland of Koryo and lives in Kara-Tur, and Areum practices law. he wanted to go into bill-drafting for public works, but the powers-that-be in Baldur's Gate were like hmm seems like a conflict of interest, since your family operates primarily as a construction magnate, so he ended up specializing in trade policy. this means he's had the pleasure of dealing with mister arms dealer Lord Gortash over the years.
his wife and the love of his life is Narae, a renowned wizard and magic theorist, and they have one son: Sarim.
...or two sons, since Areum's longtime animal companion is the grey parrot, Cath. Areum loves birds and maintains an aviary in the glass conservatory attached to the Roseroad manor.
Areum's father (Sarim's grandpa) passes away just before the events of BG3. Areum returns to work after some bereavement time, and finds that Gortash has specifically handed him a weird case that needs immediate attention. irritated and unwilling to wait for the wheels of bureaucracy to get this done (Areum wants this shit off his desk ASAP) he goes and handles the menial aspects of it himself. it includes inspecting a small storeroom of confiscated property from an Elturelian tiefling moving into Baldur's Gate.
among this guy's stuff is a scroll case. it's the only thing Areum can actually get into out of all the crates and chests. it turns out to be some kind of IOU to the owner: a djinni wish in exchange for an old favor. the djinni tied to the scroll is surprised, because Areum is not the guy who is supposed to redeem this wish, and his circumstances since asking the tief for the favor have changed drastically: he's stuck in an empty demi-plane of Air. the djinni and Areum are both dumbfounded by each other, and there isn't time to figure out wtf is going on here, because This Is When The Nautiloid Flies Over the City.
Areum shuts the scroll case in a panic and unthinkingly shoves it in his pack, tries to leave the warehouse to see wtf is going on, but guards keep him inside. Sarim, in another part of town, is abducted.
(in an alternative timeline, Areum does get out of the warehouse, and is abducted instead. he's just a fucking lawyer, so when he's on a crashing illithid ship, he quickly makes a pact with the djinni in the scroll out of necessity. congrats Areum, you are a level one warlock! eldritch blast your way back to Toril!)
in the days following the Nautiloid flyover, Areum and Narae are wrecked by the disappearance of their son. he's considered one of the countless missing civilians, and they take part in search efforts, trawling wrecked parts of the city for him. soon they're called upon to identify a body that matches Sarim's description. it turns out to not be him, but it freaks them out more than it brings them relief, and then Areum remembers the scroll. he fills his wife in on it and they open it together, to see if they can wish Sarim back.
due to wibbly wobbly Netherese magic, the djinni can't whisk Sarim from wherever he is. he cannot locate him, and even if he could, can't guarantee that bringing him here won't have dire consequences. not wanting to go back to the lonely darkness of his inexplicable prison, the djinni suggests a pact. he doesn't want to lose this tether to the Material Plane, and Areum seems a much better character than the tiefling the djinni originally owed the wish to. Narae's very skeptical of warlock pacts, but if this can help them figure out what's going on and how to get Sarim back, then it's a chance worth taking. with his wife as a witness, Areum ties himself to the djinni, and the scroll is destroyed.
somewhere else, the tiefling is PISSED that he lost the scroll. he had plans for it, damnit. (surely this won't bite Areum in the ass, right?)
incidentally: the djinni, whose name is Iram (UNINTENTIONALLY CLOSE TO AREUM, LMAO) is the father of Sarim's "ex," an air genasi named Ayaz (who was also abducted by the Nautiloid). it's a little while before the dads realize this connection. I love Dad Pact and I can talk about it forever. Iram, Ayaz, and the rascally tiefling mentioned above belong to @kota-stoker.