Harry Potters universe belongs to Joanne Rowling(Lord Voldemort and his Death Eaters are really pissed by mere idea of belonging to muggle).
Dungeons & Dragons: Council of Wyrms set, Io's Blood Island Chain and all it's inhabitants belongs to Wizards of the Coast (Dragons don't bother to even listen petty claims of human organisation which exists for less than century). I own nothing.
This is Harry Potter/Council of Wyrms crossower inspired by Rorschach's Blot's Odd Ideas: Chapter 133 Dungeons 'n Drow.
Let's see how HP universe will handle truly sapient dragon and her faithful sorcerer-kindred as their hero(Author understands that such short-lived creatures as human become kindred quite rarely and humans never become kindred but Harry Potter is Harry Potter).