Marietta had waited a long time for this, truthfully. Granger had left her with a lot of pent up aggression that she had wanted to return the favour for. But how best to start the party? She had Jayne watching which she didn't care so much about but Pandora was still there, even if she wasn't the one talking, so she had to do her best. It was good that it was Granger, then, because there was plenty that Marietta wanted to do to her to make her feel at home here in this dingy place.
She pulled out her wand and loomed over the girl who was on the floor, still in a body bind. She didn't want to leave her in that because she couldn't writhe in any pain, so Marietta removed that spell, but kept the ropes on her so she was still secured. "Y'know, Granger, I always wanted to give you something in return for what you gave me those years ago. Something similar, but then I thought that would just be too easy for you. You needed something much more interesting. But what?" she asked rhetorically, and brought her wand down in a slashing hex across the girl's arm.
"You're just so brilliant, aren't you? What would be the perfect payback for a little bint like Granger?" Marietta brought her wand down again across the girl's other arm this time, still circling around her body as she spoke. "Would you like give any suggestions to the class, Granger?" Marietta asked her and leaned down a bit pretending to listen to her.