Lavender was quickly becoming a Detention connoisseur, having served so many that she thought she ought to get the next one free. Perhaps she had started too small in picking her battles, but she felt that to put up a fuss over killing a spider and then turn around and torture a plant would label her a hypocrite. She did not want to use the Curses against living, feeling, defenceless creatures, no matter what they were.
Why she was stuck with Daphne was beyond her, but she didn't open her mouth to find out. She sat at the opposite side of the classroom and stared moodily out the window, her wand clutched so hard in her hand that her knuckles went white. Almost impulsively, Lavender rolled her eyes once Amycus walked into the classroom. Her stubbornness had made her naive to the point of stupidity, and she had no respect for how far he could push them. As far as Lavender was concerned, she had put up with his Detentions so far, and he couldn't do much worse to her. Of course, she was wrong.
Lavender stood up, but not because he told them to. She stood because she had a sudden urge to run. "You can't be serious," She said, looking from Daphne to Amycus. "If I refused to use that Curse against a plant, what makes you think I'm going to use it on a person?"