Prologue

Train Heartnet, the former Chronos number XIII Kuroneko, honestly hadn't known he had an older sister that had been given up for adoption because his mother had been too young to take care of her, and that she had been raped by her best friend's father. It had been Sven to discover this tidbit of information, and inform him of Sawada Nana, wife to Iemitsu, the Young Lion of the Vongola, and their External Advisor. To all indications Nana had no clue what her husband's real job was. By the time he made it to the Sawada home in Namimori his older half-sister was dead, and his niece would have been next if he hadn't slipped straight into Kuroneko mode. Hades made short work of the Idiots that had gone after his only remaining family. He does find out the Idiots do have bounties, which means the Sweeper was still going to get paid for dealing with such Trash.

With help from the Sweepers he proves that he is in fact Nana's younger half-brother, and gains custody of his niece when his brother-in-law can't be bothered to answer the damn phone, or any missives sent to him either. If the Vongola weren't going to protect little Shizu then he would. First he would need to set up some place permanent as a home, Shizu would need stability, therapy, and time. She could be homeschooled for a little while. He finds a decent home in Azumano, and settles in with Sven, Eve, and Shizu. The Sweepers provide the psychologist for Shizu, one that specialized in children traumatized by things like seeing their parents murdered in front of them.

Train would never regret his decision to settle in Azumano, or buy the house next door to the Niwa Family. As Daiki noticed a very troubling seal on Shizu, one he and his daughter researched extensively on how to remove. The Vongola were going to be in for one helluva surprise, as Shizu would be trained as an assassin/sweeper by Train, and Phantom Thief by the Niwas.

Seven Years Later:

Shizu grins outright at the horrified exclamation from Daisuke on his fourteenth birthday. Emiko had filled her in, since she suspected that Shizu would be the trigger for Daisuke and Dark. It was unusual, but it had happened before. Shizu's birthday had been a little less than a month before, and she takes in the taller form with violet hair and eyes. She gets her paintball sniper rifle ready, and slips out before her friend can. Well, she had accepted Daisuke's confession, but she also wanted to meet Dark. It was Dark himself that came to retrieve her after she allowed him to escape so easily, " It's not often my Tamer and I have the same trigger. "

" Emiko suspected that might happen. Now, can we get out of here. Uncle Train doesn't mind if I help you out. Hell, he started out as an assassin, then he became a Sweeper/Bounty Hunter. " Shizu deadpans.

Dark cackles merrily at this, because honestly, Shizu was perfect for Daisuke. Though even he had been pissed that such a piss poor seal had been put on a Sky Flame of that purity, that was active. Thankfully Daiki and Emiko did find a way to keep people from noticing she had been unsealed, and to keep Sky Attraction from being a problem as well.

Chapter 1

Daisuke yawns when he wakes up for the day, not even reacting to Shizu's presence beside him. Sven, Eve, and Train had gone to help out an old friend of theirs, Rinslet, leaving Shizu with his family. Growing up with Train's influence meant this Daisuke Niwa was not nearly as shy. He'd still blush when seeing Shizu in a bikini, and in their shared mindscape even Dark reacted to that stimuli. Yes, Dark was an unrepentant flirt, but Shizu was the first female since Harada Rika that he'd felt anything for. The mere fact Shizu didn't mind them sharing her, they were the same technical person, well, it was her that had kept him from being sealed back into the Black Wings because she had Harmonized with him as her Cloud, and Daisuke as her Rain.

Train had been the one to teach Daisuke how to shoot, as he put it, just because he knew how to use a gun didn't mean he had to use it. Daisuke had learned how to wield a sakabato as his weapon. He was in fact descended from Himura Kenshin, he whom had been known as Hitokiri Battōsai in the Bakumatsu. Honestly he had no problems with Train having been a former assassin turned Sweeper. It had been a shock to realize the Hiten Mitsurugi-Ryū was still being taught. Emiko had no problems with signing her son up for lessons, and like Kenshin his light frame allowed him to utilize the style to its fullest, including the double Battōjutsu using the sword and the sheath. Daisuke did have a katana as well, that could handle his Flames, just in case the Vongola decided they wanted Shizu back.

Anyone that even attempted to take Shizu from him would be met with lethal force. Dark was in agreement with that, as the Mafia was full of hardened killers. The Vongola hadn't protected Shizu and her mother when it counted. Train had left no forwarding address behind, and the Sweepers had made damned certain no names were mentioned either. This meant that the Vongola honestly had no idea what had happened to their External Advisor's Family, and Train, with help from the Niwa Family, had left plenty of false trails. If they wanted his niece they would have to earn her. He was sincerely hoping she would have all of her Guardians before she was found. Hell, Eve was her Lightning Guardian, and the genetically engineered bioweapon had actually cackled when she woke up her Flames, and turned them Useful. Train had honestly been terrified in that moment. Eve was already a beast to put down, add Lightning Flames into that as well...Verde loved the girl, though not even the Lightning Arcobaleno was stupid enough to mess with someone closely associated with Kuroneko.

Verde had taught her how to use her Flames, and upgraded her nanites as well. Daisuke remains still as Shizu snuggles in closer to him. Nightmares had plagued her sleep, not enough to wake her, but enough that his mother forewent her usual wake up method for them. That and Shizu was nasty when woken up before she wanted to be. Much like Train she was a lazy cat, and she did not like her sleep interrupted for Stupid reasons. The one and only time Emiko woke her up in her usual way on a weekend where she could sleep in...Shizu responded in kind, and took control of the traps in the Niwa home. Dark had been howling in their shared mindscape at the fact Shizu made Emiko go through the damned traps. Hell, she trapped Emiko's room, and only Emiko was affected as well. Kosuke couldn't find it in himself to pity his wife, she brought it on herself by messing with the Kuroneko's Kitten.

Shizu was very much like her uncle, an uncle that was there for her, protected her, taught her how to defend herself. She did love the lessons on being a phantom thief, hell, Dark loved the fact that she had no qualms about helping him either. Daisuke, originally had not liked the family business, but then Train had revealed Shizu's heritage. That woke up the sleeping warrior that had been hiding inside of Daisuke. He had inherited his red hair from Himura Kenshin after all.

Namimori:

Reborn, the World's Greatest Hitman frowns heavily when he reaches the Sawada home, and finds the old bloodstains. He breaks into the police station, and curses Iemitsu's incompetence. His wife had been murdered, apparently had been given up for adoption, and her younger half-brother had been granted custody of Shizu. It had only been the brother's intervention that saved Shizu as well. Apparently he happened to be a Sweeper. Had Reborn known Nana's half-brother was in fact the retired Kuroneko...he'd really be swearing. Kuroneko was one assassin/eraser no one wanted to deal with. Being good enough to earn a number in the Chronos Numbers, there was a reason why the Vindice did not mess with Chronos, or retired numbers either. They always went after the absolute worst scum of the Earth.

The Hitman turned Home Tutor calls Timoteo to fill him in on what he had learned. It would take six months to track Shizu down, because her name had been legally changed, and she wore contacts that changed her eye color to gold, she had needed to reinvent herself, and her therapist actually agreed with the idea. The further she distanced herself from the girl she had been the better. Of course, Train had no problems with training his niece in acrobatics, and more to the point had actually signed her up for gymnastics lessons as well. Like him she was very agile, could shoot gun from any angle, and mastered more than one type of firearm as well.

Azumano:

The fifteen year olds make their way into the kitchen safely, though Shizu's dart gun received a lot of use on the damned inflatable, and infantile traps Emiko favored. Emiko would have said something, but Shizu now had her paintball gun pointed at her, a dark look in her eyes. Daisuke smirks while Dark cackles in the mindscape. Shizu fit perfectly with a family of phantom thieves, though Daisuke had worked his ass off to learn several languages. He and Dark were in agreement that the Vongola Half Rings needed to be grabbed up before some got Stupid. Hence why he had no problems with being a phantom thief. Stealing from the Vongola, oh, that would really get Dark's name out there. Even better, was the fact they planned to make a proper spree of it while his mother and Shizu enjoyed a month long spa visit.

No way in Hell was Daisuke allowing his girlfriend to go anywhere near Italy. The teens eat their breakfast, and then dress for a day in the black markets. Dark took over for this, mostly because he had reason to be there while Daisuke didn't...yet. Shizu went there all the time with Train, mostly to hopefully find her Guardians, as she did not want them to be civilians. That, and if she found them all before the pain in the ass known as Reborn showed up all the better. Then again, none of them knew she already had her Storm in Rinslet Walker, her Flames would switch from Latent to Active very shortly. Shizu was even receiving training from a female oyabun on how to run a Organized Crime group, once Shizu explained her heritage, the woman agreed to an Alliance should she be tapped for Decima.

Of course no one would ever suspect the Decima candidate to be a harmless school girl on her school's gymnastics team. Shizu deliberately made herself look meek in school, though everyone knew damned well her inner bitch was not to be fucked with. No one wanted her inner bitch to come out again. Though even Dark had enjoyed Mafia Land, and they had played himself off as a Dark Mousy fanboy, one that cosplayed as his favorite thief. Colonello had been so put out that Dark, Shizu, and Train had all gotten through his obstacle course like it was mere child's play. Then they critiqued the poor sods that went after them. Daisuke had been laughing his ass off in his mindscape. Kuroneko was still a well known name, and had an open invitation to Mafia Land. They were just considered his apprentices.

Dark would never sully his reputation with murder. He was a Phantom Thief dammit. If it came down to a Ring Battle he'd easily be able to steal that damned ring from his opposite Cloud. His specialty was item reclamation, and if he couldn't steal half of a damned gaudy ring then he needed to retire. Daisuke had taken up the blade to defend their Sacred Maiden, yes, he had a katana, but he preferred his sakabatō. Daisuke would tarnish his hands with blood if there were truly no other way. Still, the mere fact Daisuke had worked his ass off to learn Spanish, Italian, French, German, Russian, Romanian, Portuguese, Latin, Chinese, and Pashto just meant that they were more than ready to go steal from the Vongola and the CEDEF.

Disclaimer: I do not own Katekyo Hitman Reborn, Black Cat, or D N Angel.