Sonia feels a twinge of guilt at that look, at his obvious discomfort, but her curiosity keeps hitting the override button, so she just listens raptly, watching his face, her own expression shifting into sympathy. Useful for his cover, of course. Somehow, none of this comes as a great surprise -- someone like Byerly, at odds with a high Vor family in direct descent of the Count? Color her shocked. But it's a vague enough account that Sonia reaches to cover Byerly's hand with her own and ask, "What happened?"