Stands for Elliot/Olivia, referring to the two main characters of Law and Order: Special Victims Unit. Over the nine years that Detectives Elliot Stabler
and Olivia Benson
have been partners, they've built up an army of e/o shippers who are madly awaiting the day that the pair become romantically involved. This day WILL come before the series ends, otherwise Dick Wolf
(the show's creator) is likely to be hunted down and killed by a mob of angry fans. Hopefully this day will include lots and lots of e/o sex, and possibly marriage and children in the not so distant future.
"did you notice the way that Elliot drank out of Olivia's glass of orange juice?"
"of course i did, any true e/o shipper would notice that first exchange of saliva between the sexiest detectives of all time... "
(Reference to episode "Stalked" from Season 1)