From a family whose blood was so pure they'd been included in the Sacred 28, Julius Selwyn had no reason or intention to sink to even looking at a muggleborn witch, and for 25 years of his life he didn't. Until, that was, he met the Japanese witch Kagome Hakumo.
Their relationship was unexpected, to say the least, but with Julius capable of causing serious damage to the family name his parents made the decision to refrain from disinheriting him with two conditions: Hakumo had to pretend to be pure-blooded, and she had to sign a prenuptial agreement. Both agreed to this, though Hakumo was a little concerned in regards to the prenup, and they were married a few months later, when she became pregnant.
11 years and five children later, Julius got home early from his high-up ministry job to find his wife in bed with a man he'd never even met. The divorce was filed as soon as he could get it, citing his wife's adultery as the public reason for the divorce. Privately, he couldn't really care less - he'd fallen out of love with Hakumo years before and had been waiting for a good reason to divorce so he could marry his mistress, Kim Hae-Soo.
The prenuptial agreement saved the Selwyns' family fortune, but there was no such barrier to save Hakumo's reputation. The only thing that stopped her ex-husband from declaring her real blood status was his love of their children. Oh, and his regard for his family reputation.
It caused a stir in pureblood society when, only six months after divorcing his first wife, Julius Selwyn remarried, this time to a pureblood from South Korea, Kim Hae-Soo, who the general public believes he met a week after his divorce. That's not true - he had, in fact, been seeing her for years after meeting her at her fourth husband's funeral.
This wedding was remarkable not only because of its proximity to his divorce but also because of Hae-Soo's reputation in wizarding England: she'd had six husbands before marrying Julius (aged only 28), each richer than the last, and each had died in mysterious circumstances, leaving all their money to her. It helps that Hae-Soo is gorgeous - it's been speculated that there was a veela somewhere in her ancestry, but both she and her family deny this and there's no record of it, so we must conclude that she just got really lucky with her genes.
Cassius Lucien Selwyn and his twin, Calliope Luana Selwyn, were born a little more than a year after their parents' marriage, the youngest of their father's children and eldest of their mother's. Cassius' whole childhood he's suspected they were accidental on his mother's part, because in her six earlier marriages she'd never once gotten pregnant and she once told him, aged five, that children were a liability. It's not that he doubts his mother's love for them - in fact, he's fairly certain they're some of the only people she loves - it's just a fact. Cassius and Calliope Selwyn were a happy accident. As was their little sister, Pandora.
Calliope could never discern growing up if she was lucky to have her father present; his uninterested attitude left much to be desired and she even found herself turning to uncles or the older men in her life to substitute as father figures. Whilst her intentional ways of trying to get his attention often failed miserably, her father's hand waving her away was a far too common sight for the young child, her first magical experience definitely did and to say she wished she could be ignored in the moment was, by far, an understatement. Having become upset from yet another futile attempt to make her father converse with her, Calliope had stormed around the house before settling in the dining room, kicking her legs in the air as she crossed her arms. A crystal bowl, one her father had bought her mother some time ago, laid in the centre of the table and all Calliope remembers is that one moment it was there, pristine and immaculate as ever, and the next it had shattered into enough shards that even she was harmed from it. Though seven years old, she was punished as if she was far older and that cemented the decline of Calliope ever attempting.
In fact, ask Calliope now and she'd gladly tell you that Cassius being there was a blessing; her elder siblings would try and emulate a full-sibling bond but it was too painfully obvious that she, Cassius and Pandora were different. That never stopped her from being intrigued by them and, perhaps led by Cassius own idolisation of them, she began to emulate their behaviour and grew closer to being just as narrow minded and prejudiced as they were.
Though overbearing, Calliope never tired of her mother's seemingly omnipresent quality. Sure the lack of friends besides her siblings could get tiring and, well, lonely, but Calliope was quickly learning how to manipulate someone and on the more personal note, her mother more than made up for the lack of her father. Calliope would play to her mother's wishes and found life to be rather amusing, especially when she would test how far her mother's love would go. Although it was a game that, more often than not, backfired on her, Calliope still had fun. The lack of friends did allow her, however, to channel her energy into the arts. Sure studying was fun and being tutored alongside Cassius made it all the more bearable, Calliope threw herself into learning how to paint, how to play the piano and harp and even going as far as to lodging her feet into the French language with dreams of reading the untranslated copy of Les Misérables. Interest in jinxes and hexes had piqued early on in her studying of magic, mostly because Calliope found them intriguing and desired to see effects in practice and not just as words on a page.
Turning eleven and receiving her Hogwarts acceptance letter was perhaps, by far, the best part of Calliope's life up until that point. After so long she was able to finally put what she had learnt into practice and just the mere thought motivated her far beyond anything else. Promptly being sorted into _____, Calliope was able to finally spread her metaphorical social butterfly wings and have friends. Whilst her most trusted and truest friend remained Cassius, Calliope found herself within the popular girls group and, at that, a leading member. For her, Hogwarts was what she felt like her life always should've been like. Her favourite part, without a doubt, was duelling.
She and Cassius had decided to pick it up - Calliope doesn't know what made them make the leap for it, but she's grateful they did - and the two quickly displayed their flair for the art. A quickly renowned double team, they seemed to make the phrase 'twin telepathy' a reality. With her casting the offensive spells and Cassius being a defensive tank, the two established themselves as a threat of a team, even winning a few inter-school championships.
The end of First Year was a weird time for Calliope. Her dear father had passed and whilst many mourned, Calliope could only find herself faking a sadness. She had little remorse and she constantly wondered if it showed. She cared not where his money went (really, not when her mother was as rich as she was) and could happily disassociate him from her life. She mostly felt weird when rumours began which led to Cassius following their sister Aline to Japan. Though grounded in Hogwarts with a duelling career, friends and good grades, Calliope found herself lost and requested a transfer to Beauxbatons.
From second year until the end of fourth year, Calliope attended Beauxbatons and was sorted into Ombrelune. She found it easy to reestablish herself within Beauxbatons' social hierarchy and happy continued her duelling career; even facing off against some Hogwarts students along the way. Though she had heard of Cassius arrival on the onset of fourth year - the two, though apart, never lost contact through muggle phones and owls - she decided to finish her third year at Beauxbatons, stating that three was a good number to end on. Recently, she's back in the UK and ready to resume at Hogwarts where she left off.