The Blacks all carry a spark of greatness, but it is intertwined with madness too. It proved certainly true for Bellatrix Black. Possessing a great beauty, prodigious power and a great aptitude for magic, she exemplified the best and the worst of the Blacks. As a witch in good standing, she respects magical prowess, something her parents thought meant that she agreed with their ideals. After all, what mudblood could stand up to a pureblood. Imagine their surprise, when they arranged her marriage with Rodolphus Leastrange. Bella, having met both him, his brother and Lucius Malfoy, declared him to be a feeble mockery of a magical and proceeded to open him from balls to brain. Even so, she declared, she couldn’t find a speck of greatness in him. Since she then declared that any other attempts to set her up with weaklings would result in her gelding her father and choking her mother with the cut off appendages, the Blacks wisely decided to let Bella go. She went on to become of the most recognized and decorated Bounty Hunters in the world, always looking for a greater challenge, looking for a wizard wielding real power.
Wizarding Britain has forgotten Bella Black, but Bella hasn’t forgotten her home country. Upon hearing of a boy having repelled over a hundred Dementors with a single spell, a boy whose godfather was her own cousin, Bellatrix seeks Harry out. Being the force of nature she is, neither the Dursleys nor any magicals are able (or willing) to stop her from taking Harry into her care, especially since Sirius supports her.
Harry arrives quite changed for his fourth year at Hogwarts, wielding a broader arsenal of spells and with reflexes faster than an attacking snake (literally, that’s how Bella trained him). He leaves quite an impression on his schoolmates and the visiting students. Recognizing a brave soul in him, Fleur Delacour befriends him. Yet even she is poorly prepared for all the drama in Harry’s life.