Character from enders-game by Orson Scott Card
Colonel and later Colonel Commandant of Battle School, the man who recruited Ender and manipulated him into becoming humanity's weapon.
Graff is a complex figure who genuinely cares about the children under his command but believes the survival of the human race justifies any sacrifice. He isolates Ender from his peers, engineers conflicts to toughen him, and ultimately deceives him into commanding the real fleet against the Formics.