"Perhaps," he replies noncommittally. Truth be told, he doesn't like unanswered questions, and curiosity had been niggling at him when she first came to him, but with time it seemed less important. Now, he's simply using the incident as an excuse to avoid discussing other matters. For example, how Lucius looks on his betrayal of the Dark Lord.

He certainly wasn't thrilled on the Barge, but the mileage varied. This Lucius is fully in step.

Too, there is the issue of Martha that he has so deftly avoided discussing with - well, anyone save Narcissa and his doppelganger, and even those conversations were a result of a motivating factor in the form of Bellatrix Lestrange.

Whatever the case, he can't immediately think of anything further to say because Severus is not adept at small talk and broader conversation is impossible until he knows where he stands. Even with an enemy, he has found, he can have a fuller and more pleasant conversation than he can manage here. Old memories can't be drawn upon without possibly hitting the wall created by his own faithlessness, and new experiences seem to be out of bounds for them both.

So he remains silent, waiting to see if Lucius will pick up the thread of the conversation and direct them to a topic he deems suitable for an evening of drinking.