"At least whatever they're doing to the mudbloods in their classes we don't have to see," Draco had meant that to be encouraging, somehow, but as he said it he realized how callous it sounded. Not that he particularly cared one way or the other what was being done to them, but he didn't want his brothers having any more leverage here than they already had, either.
"No, I understand. If something happens that is too horrible, in your classes, you should let me know. I can tell Snape, he'll stop whatever it is."