"No. You don't get to come back into my life after 2 decades and expect me to be your puppet. I have a husband. A daughter. A family. And I'll be damned if you think I'm gonna let you or anyone else for that matter take it all away from me." - Rosaline Black Sawada Vongola
After her twin brother, Nick is named boy-who-lived. Rosaline is neglected, in favour of her spoiled brother. When Rosaline turns five, Sirius has enough and whisks her away to the other dimension he has been visiting regularly.
A dimension with flames, Mafia, gun wielding babies, and more importantly. A dimension with a certain future Decimo.
Wrong Boy/girl who lived.
Sirius is Shamal.
I DO NOT CARE ABOUT AGE GAPS. LOVE KNOWS NO BOUNDS IN MY OPINION!
If that wasn't a big enough hint, (I say this jokingly) there will be age gaps between relationships.
Bianchi x Shamal
Rosaline x Tsuna
Haru x Gokudera
Uni x Byakuran
Mukuro x Chrome
Ryohei x Hana
Hibari x I-pin
Nana x Reborn (Tsuna's Sperm donor can go die for all I care.)
Yamamoto x Bluebell
Aria x Genma
Bel x Fem Fran
Lal x Colonnello
Fem Viper x Fon
Advance warning: Once entering the khr world, I will follow the canon closely, well adding in some romantic spices of my own. So spoiler alert. Also they won't be going back into the hp world until around chapter 300 - 360 (Yes, it will be that long). Time flows differently between the two worlds so I intend for it to be around 4th year by the time they are summoned there.
With all that out of the way. Please buckle up this will be a bumpy ride, (and considering how I jump from fandom to fandom, it may take me 20 years to complete.)