Based on a challenge I by Tendrarinstat, the rating will go up later. This will be highly AU, especially with the advent of HBP, but Harry will not be doing a cross over. Dumbledore is evil, Voldem...
When her parents become Death Eaters, Blaise Zabini (femaleblaise) runs away from home to avoid that fate, running to her headmaster for help, she is sent to the one place that is better protected ...