Billy still couldn't see Greengrass, but he wished he could. He bit down hard on his lip at the last comment to prevent himself from saying anything stupid, because Billy was a lot of things but he wasn't the type to do anything at wand point. Keeping Greengrass trapped in the room via a locking spell was different than holding a wand to his back; it was passive, not outwardly aggressive, and even though he was willing to do what he needed to to ensure his secrets stay safe, he couldn't imagine threatening him with magical violence (disarmament, sure, but not violence).

"Then you'll be stuck here until I find what I'm looking for," he said through gritted teeth, "because you can't leave until I do."

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