Slash, please
Albus Dumbledore/Gellert Grindelwald by somebody who's read Nietzsche. Light on the anatomical description, heavy on the two boys bursting with self-confidence, brimming with ideas to change the world. Side orders: what Gellert did at Durmstrang to enforce his new world order. Albus's love for Ariana and resentment at the prospect of being trapped in her mad little world.
Oh, and don't forget Aberforth!