This is a very specialized emoticon, meaning "I heard you fucking some dude through my bedroom wall last night and so I listened intently"
Started by a 602 with a beautiful mind on textsfromlastnight.com
In a text message...
Prima: i came home early from the bar last night.
Secunda: you did?
Prima: yeah.
Prima: 69 |D_O
Secunda: omfg. thats embarrassing.
10👍 3👎