Yap happy

When two people engage in a conversation and begin yapping to the point that a 5 minute conversation becomes a 5 hour conversation (or longer). If another party is involved, the person outside the yap happy pair may end up going unnoticed within the conversation.

Lucia: Hey sorry for not including you in the conversation yesterday, we got a little yap happy. We weren't intentionally trying to ignore you.
Mara: No worries, I know you and Darcy are chronic yappers.