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1. Wall Sex
(n): excessive chatting between members of the opposite sex using a Facebook Wall.
In some egregious case, conversation may be that resembling an instant message conversation.

Usually indicative of a fore-coming hook up, relationship, or date.
Dan: "Look at this hot girl who keeps posting on my Wall"
Ray: "What, are you two having Wall Sex now?"
Dan: "At this point it's just foreplay"
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