look up any word, like sparkle pony:
 
1.
(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"
by Anon E. Mus February 29, 2008
 
2.
When a guy pins a girl against a wall and fucks her. She is often wearing a skirt or dress. Great way to have quick public sex. Often anal. See also: skirt sex
Aly got pinned against a wall by Tim and experienced wall sex.
by Amthony April 18, 2014