Prologue: Mine

Illumi Zoldyck was told to assassinate a particular family, known as the L/n, one of the most powerful people in the underworld, when killing off the family, he finds a female, the heir to the family, he felt a weird connection towards the female and decided to take her, keeping her at the Zoldyck household. What will happen...?
(I do not own HXH, nor the cover art)