After having quite a long conversation; and after farewelling and parting from the other, one of the two in the conversation might suddenly bring up something new to talk about. This sparks an additional conversation about that topic. A post-conversation conversation can last up to a couple of hours; but normally last for about three to four minutes.
John: 'I just had the longest post-conversation conversation with Bob.'

Harry: 'cool beans.'
by robomartion September 4, 2011
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