With her arms restrained, Alecto continued to struggle for a few moments, trying to wrench herself out of his grasp.
"He wouldn't have been pleased if you had. You'd be expelled, in Azkaban, or better yet maybe Amycus would kill you in retaliation."
She stumbled slightly as he pushed her back, but remained on her feet. "You are not my better. My blood and lineage is much better than yours could ever hope to be." Still, she backed up slowly towards the way she had come from, unwilling to turn her back to him. "Watch your back, Severus. I won't forget this."
She might not have even retreated if he had not been able to stop her physical assault. For now, wandless and without the force necessary to overcome him without one, she would need to retreat back to the common room.