Antonin was frustrated when he learned she'd gone to Hogsmeade for a trunk, of all things. While he didn't let his temper get the better of him, he made it clear in no uncertain terms that he didn't approve. She shot back with a reminder that she wasn't his prisoner. After he sighed and conceded that she was right, he kissed her and begged her not to go back alone ever again. If she wanted to go, he wanted to be at her side. It was too dangerous otherwise. She promised only under the condition that he wouldn't go without her either. They would be partners or they would be nothing. Reluctantly, he agreed.