He snorted in amusement and flicked the end of his cigarette into the fire before pulling another out and lighting it up. "Well, sweetheart, I don't remember asking your opinion on the matter. You had the choice back at Azkaban, help me or die. I promised I wouldn't kill you, this is your only choice now. Death is always still an option if the idea of being one of us repulses you so much." He glared a little, just to drive the point home that if she did choose death, it wouldn't be pleasant or quick.
He took a thoughtful drag on the cigarette. "No, they won't, and there's no promise they'll leave you alone once you are changed, but you'll be able to defend yourself better." Besides, he wasn't going to let them have any fun with his catch. Not after he'd done all the work to get her there. "Stick close to me and you'll be fine." he added as an after thought.