Ah... Regulus is reborn in Reborn as Tsuna's twin sister? I just had to try my hands on this xD
Warnings: Fem!Regulus, AU, Tsuna cuteness.
The Young Lion
Regulus Black died with a bitter sense of failure curling in his belly… It might be because he died embraced tightly by Inferi, or maybe because he died without ever admitting his feelings to his elder brother – 'Hey Sirius, you were right when you bullied me because I was friends with my year mates…' – Maybe not that. Definitely not that. After all, Regulus did do the right thing in the end, where he died without any recognition and being thought of as a dastardly evil Death Eater.
No one would know the deep psychological struggles he went through. 'Mudbloods, all of them, stealing our magic, our culture, our world… they all should die and make way to a new age of glory for the unsullied… Always Pure, Regulus, you are a Black'… Were the thoughts ingrained into his very flesh by both his family and friends.
It looked like quite the obvious step, didn't it? Joining the rising Dark Lord in his campaign to free the magical world from muggles… Regulus joined his family, house and blood in this fight, though up until this turning point.
"Cousin… They're children…"
"Do it, Reggie, do it for our Lord. One or two less muggle filth in this world for our Lord to content with…"
He could still see their tiny faces flashing grin at the tip of his wand. That night was haunted by children's cries and small hands gripping at him and asking, why did you kill us? Regulus spent weeks telling himself that being offered a clean, painless death by him was a hundred times better than being tortured by his Cousin. This didn't make the nightmares any less painful.
After that Regulus took a step back.
He could understand fighting off muggles encroaching on their territory, muggles imposing their odious culture on them, they having to bend to the muggleborn's tastes so they would 'fit in'. A bunch of utter bullshit – even those developing 'technologies' so often talked about in obscure rags, about how muggles managed to go to the moon! They wiped off an entire city from existence with a 'bomb'. They now had those 'cameras' that represented an even bigger danger to the magical world!
Should they be exposed to the muggles, it would mean a second Witch Hunt. That was his fear. That was the fear in heart of practically everyone under Voldemort's banner… except for those who genuinely loved war and carnage… like cousin Bella.
Though Regulus still had a heart. He might not feel much guilt after taking down a grown adult – they could defend themselves – but children? And then it happened… That accursed prophecy, the one about a baby who would rid the world of Lord Voldemort… Regulus and everyone else in Voldemort's hideout that fateful evening when Snape brought back the news, bore witness to the biggest power burst (temper tantrum) ever seen by the current Dark Lord.
And the youngest Black son found himself at odds with Voldemort's ideology once again.
Killing innocent muggle children chaffed on his consciousness but it was but a sacrifice to be made in order to bring down the threat of those without magic – but dooming a magical babe born to magical parents (though the mother was a mudblood, she was still a very powerful witch) was a bit much… how many pureblood households struggled to birth a single child? How many of them would do absolutely anything to be able to have more than one or two children? Magical children are precious.
So Regulus dug into Voldemort' secrets… He left not one stone unturned as he scavenged for answers, something to justify the now growing streak of dislike for the Dark Lord.
He found it.
Voldemort, once a bot named Tom Marvolo Riddle – admitted as a muggleborn in Hogwarts from a muggle orphanage in London (he was still Slytherin's heir though, dubious ancestry aside), but most of all Regulus found proof of something even more wicked than his admittedly dark morals supported.
Horcrux.
Voldemort definitely had one, maybe more than one.
Regulus had his proof, he had his redemption and his guilt guided him.
He died alone being embraced by decaying corpses, asphyxiated by the cold waters inside Voldemort's little cave.
…
And then he wasn't dead anymore.
Well… it was just like waking up after a long night of sleep. It was dark, and then it wasn't. Simple as that… or maybe not so much… Or maybe even not at all.
"How is my little lioness doing, who is my little-itty kitty?" A large bear of a man cooed, hovering over Regulus in such a frightening way that it took everything the Slytherin had not to cry out in fear.
"Are you done with Miruku-chan dear? Tsu-kun wants his papa too!" A woman danced into his view carrying a cute brown haired toddler, who bore a passing semblance to her. "Lemme see my Milky Kitty~!"
What in the name of Merlin's blessed left cheek is going on?!
…
Reincarnation, Regulus hates thee with a passion.
When he woke up after his memory of dying, he was quite literally inside a two years old child – why he woke up at two, he'd never know – but there he was in all his new slobbering glory and short stubby limbs. It shouldn't have been so bad because frankly? He felt tired of the Wizarding World after being forsaken by it (it did not help that he openly supported the Dark Lord at the time), and it kind of made him look forward to a new life even if his new family was Mundane and he didn't have magic this time around.
Alas, it took a lot of time and effort to actually get used to this new life.
He missed magic, he missed Kreater, he missed magic, he missed his old hag of a mother, he missed Sirius, he missed magic, he missed Hogwarts, he missed magic and lastly, he missed being male. Because his fortune wouldn't be complete without a complete plot twist. Goodbye Regulus, Black family heir and hello Miruku, two years old little tot who was barely potty trained.
It was awkward, painful, humbling and daunting all in one.
A baby's life is boring without all the new things to figure out like normal babies do – his precious little child's brain already did the favor of picking up his parents' language (Japanese!) on its own during the two years his consciousness spent sleeping so that wasn't even a factor to help him stall the boredom.
At least growing up a girl in contrast to suddenly turning into one at his mental age is bound to be less traumatizing. That's his prerogative, he's sticking by it and praying almost every night that he was never found out by his brother or friends or his brother's friends.
Another good perk?
He still landed himself a brother. And this time Regulus was not going to be such a shitty brat to his sibling – determined as he was to be the best little sister ever, Yoshi-ni-san was going to be the happiest bugger on this Earth.
"Mimi, Mimi, look!" Tsunayoshi held up his paint dripping hand in a proud wave that splattered their surroundings in whatever color he was painting prior to trying to catch Regulus-Mikuru's attention.
...