William was thinking very different things as he looked at the terrible situation outside the window. "Isabella, I'm going," he said, making it clear that he had already decided. His voice had a sense of finality that meant he was not going to be stopped, not even by her.
"But William..." Isabella felt really mixed up at this point, more than she ever had before. On one hand, she didn't want to see her own kind get hurt by him. On the other hand, she knew that her own people were the ones who started this by attacking this city full of humans.
William didn't wait for her to finish her sentence. He opened the window and stepped out into the dark night. As he left, he disappeared into the shadows, leaving Isabella alone with her complicated feelings.
Isabella looked out the window, feeling all mixed up inside. She was really torn about what to do. She wanted to be with William but at the same time, she felt a strong need to protect her own people, her own kind.