She watched him stiffen and felt her hand fall to her time turner. There were limits to every spell. The limit to her ritual was that she couldn’t go outside the realm of possibility. For example, she couldn’t tell Draco to turn into a cat and have him actually do it. He’d have to go through the difficult process of becoming an animagus and even then he might not become the right animal. As another example, one she had tested if she told him not to scream and then performed the Cruciatus Curse he would try to follow her command but wouldn’t be able to keep from it. Everything had to be possible.