There isn't an immediate response. There is nothing left to pack away, no more indications he can give to Lucius that this is not a conversation he wishes to have. So he finally resigns himself to it and mulls over a reply which might at least be adequate.

Severus isn't quite sure where he stands with his old friend, but there is something about the way Lucius keeps pushing which suggests 'friendship' itself is not yet out of the question - and he could use an ally or two. The problem is, he's not sure where the other man is going with this.

"No," he replies at last. "It does not surprise me that you would cease to engage in any activity which holds no benefit for you or your family."