"Pans!" Hermione heard Draco yell as he dug his heels in to halt his desperate attempts to drag Pansy into a mad sprint, flinging out his arm, his momentum swinging Pansy away from him to tumble safely into the wet dark. And Hermione knew what was going to happen and a strangled sob burst past her lips, and her body was rooted to the ground as she watched, helpless. The curse struck just as Draco steadied himself, turned around by the momentum of getting Pansy safely out of the way, leaving him completely vulnerable, standing facing Greyback and the rest of the "wolves.