Yeah, he was fucking stealing—but how could he respond to that? Really it was best not to. Trying to justify it would be as incriminating as simply agreeing that he was, especially if Greengrass intended to report him to the authorities after this.
He heard footsteps again, causing him to freeze in place. The request Greengrass was making was... reasonable, but Billy had his reasons for being wary of it. "I won't touch you, but I don't trust you enough to put my wand away," he responded, which was the first truly truthful thing he'd said in a while. Even if he did manage to find his ingredient, he knew he had to come up with some way to stop Greengrass from talking when this was all over. Obviously memory charms were an option, but they were difficult and unpredictable, and on top if that they required the victim to stay relatively still to have their intended effect. The other choice was - blackmail, and Billy's knowledge of Fortitude Greengrass didn't suggest that there was much to work with there.
"You need to help me," he said resolutely, "You need to help me with my problem. I won't hurt you, I won't touch you, I won't do anything—and then we'll get out of here."
He heard footsteps again, causing him to freeze in place. The request Greengrass was making was... reasonable, but Billy had his reasons for being wary of it. "I won't touch you, but I don't trust you enough to put my wand away," he responded, which was the first truly truthful thing he'd said in a while. Even if he did manage to find his ingredient, he knew he had to come up with some way to stop Greengrass from talking when this was all over. Obviously memory charms were an option, but they were difficult and unpredictable, and on top if that they required the victim to stay relatively still to have their intended effect. The other choice was - blackmail, and Billy's knowledge of Fortitude Greengrass didn't suggest that there was much to work with there.
"You need to help me," he said resolutely, "You need to help me with my problem. I won't hurt you, I won't touch you, I won't do anything—and then we'll get out of here."
